EJBD
ARCHIVE
EPA
601-
R-
86-
004

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                                            TR-09-86
    A STATISTICAL ABSTRACT OF THE
      UNSEWERED U.S.  POPULATION
                               Repository Material
                              Permanent Collection
      Contract  No. 3-84-2-6908
           Submitted To:

   James Kreissel, Project Officer
   ENVIRONMENTAL PROTECTION AGENCY
     26 West Street, Clair Street
       Cincinnati, Ohio 45268
            Prepared By:

ENGINEERING & ECONOMICS RESEARCH, INC.
         1951 Kidwell Drive
       Vienna, Virginia 22180



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  oo ^
                                           TABLE OF CONTENTS
                                                                                 Page

              INTRODUCTION                                                         1

              SECTION I

                   A comparison of unsewered dwellings between 1970 and            4
                   1980: an overview


              SECTION II

                   Major features of unsewered single family dwellings            16
                   when classified by lot sizes

                   Main features of single family dwellings on lot size           19
                   of less Chan one acre when classified by rural/urban
                   location

                   Main features of single family dwellings on lot size           22
                   of less than one acre when classified by the source of
                   water supply

 ^3                Main features of single family dwellings on lot size           25
 O                of less than one acre when classified by the number of
I —                bedrooms

.3-                 Main features of single family dwellings on lot size           28
cT                of less than one acre when classified by the age of
 0°                 dwellings

                   Main features of single family dwellings on lot size           31
                   of less than one acre when classified by the value of
                   property


              SECTION III

                   Main features of unsewered single family dwellings             41

                   Main features of unsewered single family dwellings             44
                   When classified by the source of water supply
                                                   li

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                                                                   Page
     Main features of unsewered single family dwellings             47
     when classified by the number of rooms

     Main features of unsewered single family dwellings             SO
     when classified by the age of dwellings

     Main features of unsewered single family dwellings             53
     when classified by the value of property


APPENDIX A:    A METHODOLOGY TO EXTROPOLATE INCOME                  56
APPENDIX B:    SIGNIFICANCE TEST FOR DIFFERENCES OF MEANS           58

GLOSSARY                                                            59
                                     iil

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                             LIST OF TABLES
                                                                 Page

Table 1:  A comparison of salient features of unsewered           5
          dwellings between  1970 and  1980 (source:   1970
          and  1980 census)

Table 2:  Percentages of rural household population  and           6-9
          unsewered housing  units in each state/state
          group (source:  1970 and  1980 census).

Table 3:  Classification of  structures by type of sewage         10-12
          in each state/state group (source:  1980 census).

Table 4:  Classification of  population by.type of sewage in      13-15
          each state/state group (source:  1980 census).

Table 5:  Characteristics of unsewered single family            17-18
          dwellings — classification by lot sizes (source:
          1980 census).

Table 6:  Characteristics of unsewered single family            20-21
          dwellings on lot size of  less than one acre —
          rural/urban classification  (source:  1980  census).

Table 7:  Characteristics of unsewered single family             23-24
          dwellings on lot size of  less than one acre —
          classification by  the source of water supply
          (source:  1980 census).

Table 8:  Characteristics of unsewered single family             26-27
          dwellings on lot size of  less than one acre —
          classification by  the number of bedrooms (source:
          1980 census).

Table 9:  Characteristics of unsewered single family             29-30
          dwellings on lot size of  less than one acre —
          classification by  the age of dwellings (source:
          1980 census).

Table 10: Characteristics of unsewered single family             32-33
          dwellings on lot size of  less than one acre —
          classification by  the value of property (source:
          1980 census).

Table 11: Classification of  structures by type of sewage         34-37
          in each state, (source:   1970 census).

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                                                                 Page
Table 12: Classification of population by type of sewage         38-40
          in each state, (source:  1970 census).

Table 13: Characteristics of unsewered single family             42-43
          dwellings, (source:  1970 census).

Table 14: Characteristics of unsewered single family             45-46
          dwellings — classification by the source of
          water supply (source:  1970 census).

Table 15: Characteristics of unsewered single family             48-49
          dwellings — classification by the number of
          rooms (source:  1970 census).

Table 16: Characteristics of unsewered single family             51-52
          dwellings — classification by the age of
          dwelling (source:  1970 census).

Table 17: Characteristics of unsewered single family             54-55
          dwellings — classification by the value of
          property (source:  1970 census).

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                              INTRODUCTION
     The purpose of this statistical abstract Is  to  provide  demographic
and housing characteristics of the  unsewered population In the U.S.  based
on  1970  and  1980  census  data.  These  characteristics  are provided  to
assist Che  Wastewater Research  Division  of Water Engineering  Research
Laboratory in planning wastewater facilities over the upcoming decades.

     In the  abstract, unsewered population and housing units are enumerated
for each state/state group.

     Using  1980  census data,  unsewered single  family dwellings in  the
U.S. are  classified  by lot  sizes.  Within  each class  statistics  on
the following variables are provided:

     o  Total number of dwellings
     o  Occupancy status (occupied/seasonal/vacant)
     o  Plumbing status (complete/incomplete)
     o  Source of water supply (public system or a private  company/
        other sources)
     o  Bedrooms
     o  Bathrooms
     o  Occupants (adult/children)
     o  Age of adult occupants
     o  Age of dwelling
     o  Property value
     o  Household income.

Dwellings  on lot  size of  less  than one  acre  are  analyzed  in  greater
detail.   These  dwellings  are classified  by location  (rural/urban),
source of  water  supply,  number  of bedrooms,   age  and property  value
of  dwellings.  Within  each of  these  sub-classes,   statistics  on  the
variables listed above are provided.

     All  elements of  analyses  of  1980  census  could  not be  repeated
for the 1970  census due to the unavailability of the data.   For example,
1970 census data does not provide  information on lot sizes.  Rural/urban
classification is not made for all states.*  No information is available
on  number  of bedrooms  and household  income,  instead  the  information
     *The  eight  states for which  no  rural/urban  classification  is  made
are  -  Alaska, Delaware,  Hawaii, Nevada,  Rhode  Island, Utah,  Vermont,
and Wyoming.

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is  available  on number of rooms and  family  income.   Keeping these dif-
ferences in view, most of  the  analyses  of  1980 census data are repeated
for 1970 census data.

     The statistical  abstract  is divided  into three sections.  Section
I describes  the salient features of  single family  unsewered  dwellings
in  1970  and  1980.   A  table  showing  percentages  of  rural population
and unsewered housing units  in each state/state group for the  two years
is also provided.  Section II  provides  detailed analyses of 1980 census
data.  Section  III describes analyses of 1970 census data.

SOURCES OF DATA

     Public-use microdata  samples obtained from the Bureau of the Census
for 1970 and  1980 were used in the preparation of the abstract. Public-use
microdata samples are computer tapes  which contain  records for a sample
of housing units, with  information  on the characteristics  of  each unit
and  the  people in it.   For the abstract,  IT  sample was  used  for both
1970 and 1980 census.

     For the  1980 census,  each  microdata file  Is  a  stratified  sample
of  the  population,   actually a  sub-sample of  the  full  census sample
(19.4Z of all households)  that received census long-form questionnaires.
Sampling was  done household-by-household  in  order  to  allow  study  of
family  relationships and housing unit  characteristics.   Sampling  of
persons in institutions  and  other group quarters was  done  on  a person-
by-person basis.  Vacant units were also sampled.

     In preparing  this  abstract,  1Z C  sample was  used  for  the  1980
census for the  following two reasons:   (1) to  see if the classification
by  location  (rural/urban)  affected  the characteristics  of unsewered
dwellings  and  (2)  to study the trend  of unsewered  housing   units  in
the  last  decade.   The  1Z  C sample  identifies  27  states,  District  of
Columbia and eight groups of states.

     The Census Bureau  created  six  separate  1Z  samples from  the  1970
census, three based  on  the  1SZ  version  of the  1970  questionnaire,  and
three based  on the  SZ  version.   Geographic  areas  identified on  1970
microdata  files were required to have  at least 250,000  inhabitants.
One  geographic scheme  employed in  1970 identified  states,   a  second
identified SMSA's with  250,000 or more inhabitants and  similarly  large
county groups elsewhere, and the  third  identified only very large areas
but included records for "neighborhood characteristics."

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SECTION I

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     In  Che  1970 census,  data on  sewage  disposal and  source  of water
supply was available  only at  the  15?  version.   Hence,  the  151 version
which identifies states was used.  Here all fifty states are identifed.

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A COMPARISON OF UNSEWERED DWELLINGS BETWEEN 1970 AND 1980;  AN OVERVIEW

     In  che  last  ten years, both  the number and  percentage  of sewered
housing  units  have  increased.   In  1970,  out  of  68.7  million housing
units, 68.4 million  (i.e.,  70%) were  served  by  the public sewer system.
In  1980,  the total  number  of  housing units  increased  to 84.8 million.
Of  these 62.2  million  or  74Z  were  served  by  public  sewer  systems.
Table  2  shows   that  in  each state  the percentage of  unsewered housing
units have declined  in the  last ten years.

     In  spite  of  the  decline  in  the  percentage  of  unsewered housing
units,  the  absolute number of unsewered  single  family dwellings  has
increased.   In  1970, there were  18.1  million  unsewered  single  family
dwellings.  In  1980  the number increased to 19.7 million.

     In  the  last   ten years,  there has  been no  change in some  of  the
characteristics of unsewered dwellings.  For  example,  the percentage of
year round occupied  dwellings has  remained  constant  at 87Z.   The  median
number  of adult  and child  occupants remained  the  same, respectively
at two and zero.

     Some characteristics have  changed  in the last ten years.  In 1980,
the percentage  of  dwellings with complete plumbing facilities increased
to  93.2Z from  80%  in  1970.   These  has  been  a  small  increase  in  che
percentage  of  dewllings  receiving  their water supply from  a  public
system  or a private company.  This  percentage  increased from  37Z  in
1970 to  391  is  1980. The average  age of adult  occupants declined  from
46.41 years to 45.71 years  in 1980.

     It  is  not possible  to compare  the  economic status  of  households
because  in  the  1980 census, data  was collected  for  household  income
but in  the  1970 census,  family income was reported.   According  to  the
Bureau  of the   Census,  household  Income differs  from  family  income  by
including  income  received  by  all household members  15 years  old  or
over, not just those related to the householder.*

     Due to  an explosion in  property values in  the decade of the seventies,
it  is  not  very meaningful  to  compare the  average property value  of
dwellings in 1970 and 1980.  In the 1070 census, the  highest classification
for property value was  S50,000  or  aore.  This classification  was  raised
to $200,000  or more in the 1980 census. Any other comparison of statistics
derived  from the  1970  and  1980  census data is  not  possible because
in  the  former case,  dwellings are  analyzed  Irrespective  of the  lot
size, whereas  in  the latter,  dwellings on  lot size  of less  than  one
acre are analyzed.
*For a detailed distinction in the two definitions refer to glossary.

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                                TABLE  1




        A COMPARISON OF SALIENT FEATURES OF UNSEWERED DWELLINGS




             BETWEEN 1970  AND 1980 (SOURCE:  1970 AND 1980)
                                        1970 Census    1980 Census
Total number of unsevered housing
units*
Total number of unsevered single
family dwellings*
Number of unsevered dwellings
occupied year round*
Number of unsevered dwellings with
complete plumbing facilities*
Number of unsevered dwellings
receiving vater supply from a public
system or a private company*
Average age of dwelling (in years)
Median number of adult occupants
Median number of child occupants
Average age of adult occupants
(in years)
202,527
181,242
157,296
145,502
67,419
27.76
2.00
0.00
46.41
225,529
197,585
172,961
184,156
76,519
27.02
2.00
0.00
45.71
*Numbers are in hundreds.

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                        TABLE 2




PERCENTAGES OF RURAL HOUSEHOLD POPULATION AND UNSEWERED




        HOUSING UNITS IN EACH STATE/STATE GROUP




            (SOURCE:  1970 AND 1980 CENSUS)

STATE
Alabama
Arkansas
California
Colorado
Connecticut
District of
Columbia
Florida
Georgia
Illinois
Indiana
Kentucky
Louisiana
Michigan
Mississippi
RURAL HOUSEHOLD
1970 CENSUS
42
50
9
22
22
0
19
40
17
36
48
34
26
57
POPULATION
1980 CENSUS
40
49
9
20
21
0
15
38
17
36
50
31
29
53
UNSEWERED
1970 CENSUS
49
47
13
19
38
1
39
42
17
38
49
32
34
52
HOUSING UNITS
1980 CENSUS
46
43
11
12
33
1
28
40
15
35
46
29
31
44
                                                  (continued)

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TABLE 2 (continued)

STATE
New Jersey
New York
North Carolina
Ohio
Oklahoma
Oregon
Pennsylvania
South Carolina
Tennessee
Texas
Virginia
Washington
Ve'st Virginia
Wisconsin
Maine
New Hampshire
Vermont*
Massachusetts
Rhode Island*
RURAL HOUSEHOLD
1970 CENSUS
11
14
57
25
32
33
29
54
42
20
37
28
62
35
50 )
44 (
- }
~\
POPULATION
1980 CENSUS
11
15
53
27
33
32
31
47
40
20
35
27
64
36

54

16
UNSEWERED
1970 CENSUS
18
23
55
26
27
39
29
55
48
22
39
36
49
32
*)
"
37)
29 I
37)
HOUSING UNITS
1980 CENSUS
14
23
54
24
27
32
27
47
44
19
35
33
49
31

55

29
                              (continued)

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TABLE 2 (continued)

STATE RURAL HOUSEHOLD POPULATION UNSEWERED HOUSING UNITS
1970 CENSUS 1980 CENSUS 1970 CENSUS 1980 CENSUS
Maryland 23 |
Delaware* - )
Montana 47 )
Idaho 45 >
Wyoming* - /
Minnesota 34 >
Iowa 44
Missouri 30 j
'
Kansas 34
Nebraska 38
South Dakota 56
North Dakota 58 /
Utah* - |
Nevada* - j
Arizona 20 )
New Mexico 30 j
23)
21 } 21
.26)
39
45 44
25,
\ 32>
"
1
^ 37 24
25
37
38 >

35




> 27



18 I
15 } 14
15)
24)
20 J 23
29)
                             (continued)

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                            TABLE 2 (continued)
STATE          RURAL HOUSEHOLD POPULATION     UNSEWERED HOUSING UNITS
               1970 CENSUS    1980 CENSUS     1970 CENSUS 1980 CENSUS
Alaska* - )
t 2C
Hawaii* - )
38)
-1
24
*  - In the 1970 census, distinction between the rural/urban
     classification is not made for these states because there
     are less than 250,000 people in one or the other category.

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SECTION II

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                                     TABLE 3




CLASSIFICATION OF STRUCTURES BY TYPE OF SEWAGE IN EACH STATE/STATE GROUP*




                              (SOURCE:   1980  CENSUS)

STATE /STATE ALL
GROUP STRUCTURES**
Alabama
Arkansas
California
Colorado
Connecticut
District of
Columbia
Florida
Georgia
Illinois
Indiana
Kentucky
Louisiana
Michigan
Mississippi
New Jersey
New York
15,458
9,507
98,599
12,699
12,493
3,104
45,788
21,722
45,920
22,388
14,720
16,457
37,926
9,770
29,092
73,222
HOUSING UNITS
TOTAL SEWERED UNSEWERED
14,681
8,991
92,935
11,956
11,603
2,785
43,831
20,299
43,210
20,933
13,688
15,494
35,949
9,131
27,739
68,734
7,687
5,166
82,827
10,266
7,829
2,762
31,457
12,109
36,575
13,655
7,335
11,067
24,865
5,120
23,987
53,062
6,994
3,825
10,108
1,690
3,774
23
12,374
8,190
6,635
7,278
6,353
4,427
11,084
4,011
3,752
15,672
UNSEWERED HOUSING
UNITS
SEPTIC TANK/ OTHER
CESS POOL MEANS
6,252
3,415
9,541
1,505
3,708
6
12,009
7,578
6,278
6,967
5,172
4,0«»1
10,531
3,297
3,614
14,996
742
410
567
185
66
17
365
612
357
311
1,181
336
553
714
138
676
                                    10
                                                               (continued)

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TABLE 3 (continued)

STATE /STATE ALL
GROUP STRUCTURES**
North
Carolina
Ohio
Oklahoma
Oregon
Pennsylvania
South
Carolina
Tennessee
Texas
Virginia
Washington
West Virginia
Wisconsin
Maine,
New Hampshire,
Vermont
Massachusetts,
Rhode Island
24,724
43,376
13,265
11,422
48, 947
12,605
18,591
58,950
21,996
18,003
7,832
19,959
12,005
28,127
HOUSING UNITS
TOTAL SEVERED UNSEVERED
22,777
41,090
12,365
10,844
45,975
11,545
17,479
55,544
20,230
16,910
7,484
18,671
11,112
25,807
10,501
31,176
9,058
7,386
33,667
6,098
9,882
44,813
13,231
11,271
3,808
12.818
5.016
18,364*
12,276
9,914
3,307
3,458
12,308
5,447
7,597
10,731
6,999
5,639
3,676
5.853
6,096
7,443
UNSEWEREO HOUSING
UNITS
SEPTIC TANK/ OTHER
CESS POOL MEANS
11,292
9,232
3,112
3,316
11,312
4,973
6,863
9,750
6,052
5,442
3,037
5,348
5,532
7,288
984
682
195
142
996
474
734
981
947
197
639
505
564
155
                                 (continued)
    11

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                               TABLE 3 (continued)
STATE/STATE     ALL
   GROUP    STRUCTURES'
                                 HOUSING UNITS
                              UNSEWERED HOUSING
                                   UNITS
TOTAL
                                                        SEPTIC TANK/ OTHER
                                    SEWERED   UNSEWERED  CESS POOL   MEANS
Minnesota, 73,825 68,589 50,336 18,253
Iowa, Missouri,
Kansas ,
Nebraska,
South Dakota,
North Dakota
Maryland, 19,210 18,108 14,219 3,889
Delaware
Montana, Idaho, 9,416 8,937 5,815 3,122
Wyoming
Utah, Nevada 8,682 8,305 7,169 1,136
Arizona, 16,961 16,215 12,528 3,687
New Mexico
Alaska, Hawaii 5,535 4,975 3,769 1,206
16,430 1,823
3,612 277
2,857 265
1,064 72
3,181 506
915 291
 *Numbers are in hundreds.

**The numbers indicated under all structures include group quarters.   All
  group quarters are sevred.
                                   12

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                                     TABLE 4




CLASSIFICATION OF POPULATION BY TYPE OF SEWAGE IN EACH STATE/STATE GROUP*




                              (SOURCE:   L980 CENSUS)

STATE/STATE
GROUP
Alabama
Arkansas
California
Colorado
Connecticut
District of
Columbia
Florida
Georgia
Illinois
Indiana
Kentucky
Louisiana
Michigan
Mississippi
TOTAL
38,272
22,410
231,606
28,185
29,965
6,042
95,915
53,253
111,745
53,335
35,578
41,271
90,304
24,640
POPULATION UNSEWERED POPULATION SERVED
BY BY
SEPTIC TANK/ OTHER
SEWERED UNSEWERED CESS POOL MEANS
19,292
12,593
206,436
24,297
19,333
5,994
65,744
30,643
93,588
33,518
17,905
29,118
63,762
13,516
18,980
9,817
25,170
3,888
10,632
48
30,171
22,610
18,157
19,817
17,673
12,153
27,042
11,124
17,152
8,925
23,918
3,704
10,479
17
29,555
21,069
17,536
19,258
14,715
11,416
26,584
9,203
1,328
892
1,252
184
153
31
616
1,541
621
559
2,958
737
458
1,921
                                                               (continued)
                                    13

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TABLE 4 (continued)

STATE /STATE
GROUP
New Jersey
New York
North Carolina
Ohio
Oklahoma
Oregon
Pennsylvania
South Carolina
Tennessee
Texas
Virginia
Washington
West Virginia
Wisconsin
Maine,
New Hampshire,
Vermont
Massachusetts,
Rhode Island
TOTAL
72,427
171,088
56,692
105,759
29,353
25,809
115,819
30,218
44,830
139,458
51,901
40,274
19,164
45,828
24,606
64,503
POPULATION UNSEWERED POPULATION SERVED
BY BY
SEPTIC TANK/ OTHER
SEWERED UNSEWERED CESS POOL MEANS
61,498
129,203
25,331
77,221
20,750
16,887
83,494
15,077
24,287
113,181
33,131
25,768
9,110
31,713
11,562
44,527
10,929
41,885
31,361
28,538
8,603
8,922
32,325
15,141
20,543
26,277
18,770
14,506
10,054
14,115
13,044
19,976
10,641
40,980
29,309
27,170
8,220
8,753
30,940
13,955
18,906
24,321
16,417
14,292
8,628
13,715
12,573
19,727
288
905
2,052
1,368
383
169
1,385
1,186
1,637
1,956
2,353
214
1,426
400
471
249
                               (continued)
     14

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                               TABLE 4 (continued)
STATE/STATE                 POPULATION        UNSEWERED POPULATION SERVED
  GROUP                                              BY          BY
                                                 SEPTIC TANK/   OTHER
                   TOTAL    SEWERED   UNSEWERED   CESS POOL     MEANS
Minnesota, Iowa,  166,893   120,782    46,111       43,463      2,648
Missouri,
Kansas,
Nebraska,
South Dakota,
North Dakota
Maryland ,
Delaware
Montana, Idaho,
Wyoming
Utah, Nevada
Arizona,
New Mexico
Alaska, Hawaii
47,225
21,573
22,427
39,496
13,186
36,412
13,779
19,340
30,640
9,921
10,813
7,794
3,087
8,856
3,265
10,097
7,515
3,008
7,800
2,797
716
279
79
1,056
468
^Numbers are in hundreds.
                                    15

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          MAJOR FEATURES OF UNSEWERED SINGLE FAMILY DWELLINGS

                      WHEN  CLASSIFIED BY LOT SIZES

                              1980 CENSUS
     Unsevered  single family  dwellings  were  classified  on  Che  bases
of these  lot  sizes:  (1) less  than  one  acre,  (2)  between one and nine
acres, and (3) ten or more acres.  46* of the total unsewered dwellings
were  located  on  lots  of less  than  one acre  and  232 were  on  lots  of
more  than 10  acres.  The  remaining  31Z were  located  on  lots of  1  to
9 acres.

     Of  dwellings on  lots  of  less  than one  acre, 83Z  were occupied
year  round,  94Z  had complete  plumbing  facilities  and  571 obtained
their water supply from a public system or a private company.

     Of dwellings on  lots of  between 1 and 9  acres,  92%  were occupied
year  round,  94Z had  complete  plumbing facilities  and  29Z  were  served
by a public system or a private company.

     Of dwellings on lots of  10 or more acres 89?  were  occupied year
round,  902  had  complete plumbing  facilities  and  only  142 received
water from a public system or a private company.

     The size of a dwelling, both in terms of median number of bedrooms
and bathrooms  does not  vary  with the  lot  size.   The  same  holds  true
for median number of adult and child occupants.

     Other parameters in the table, namely, average age of adult occupants,
average age of dwelling, average value of property and household income
vary  with the  lot  size.  Dwellings  on  lot sizes  of between one  and
nine  acres  are  significantly*  younger  and  more  expensive  than  those
on other  lot  sizes.   Correspondingly,  average household  income  is
significantly  higher for dwellings  on  lot  sizes of  between one  and
nine acres than on any other  lot size.   Also,  on average  the occupants
on these dwellings are significantly  younger than occupants of dwellings
in any other category.
^Throughout the abstract, the word "significantly" is used in the
 statistical sense.  A statistical test (described in Appendix B)
 is used to test the significance of the difference between means
 at the 5Z level of significance.
                                   16

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                                  TABLE 5

CHARACTERISTICS OF UNSEWERF.D SINGLE FAMILY DEWLLINGS — CLASSIFICATION

                    BY LOT SIZES (SOURCE:  1980 CENSUS)
Characteristics of
Dwellings
Less than
one acre
 LOT SIZES

1 to 9 acres
10 or More
  acres
Total Number of dwellings*      91,164

Number of dwellings*
   occupied year round          76,118
   vacant year round             8,206
   with seasonal occupany        6,840

Number of dwellings with*
   complete plumbing            85,802
   Incomplete plumbing           5,362

Number of dwellings with water
supply from*
   public or private company    52,012
   other source                 39,152
               61,551
               56,741
                3,127
                1,683
               58,092
                3,459
               17,987
               43,564
                  44,870
                  40,102
                   3,563
                   1,205
                  40,262
                   4,608
                   6,520
                  38,350
Number of bedrooms
mean
median
standard deviation
Number of bathrooms
mean
median
standard deviation
Number of adult occupants
mean
median
standard deviation

2.70
3.00
0.88

1.30
1.00
0.47

1.73
2.00
1.05

2.88
3.00
0.89

1.36
1.00
0.49

1.97
2.00
0.93

2.91
3. no
0.98

1.20
1.00
0.47

1.89
2.00
1.00
                                                             (continued)
                                   17

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                                 TABLE 5 (continued)


Characteristics of
Dwellings
Number of children
mean
median
standard deviation
Age of dwelling (in years)
mean
median
standard deviation
Value of property
(in dollars)
mean
median
standard deviation
Household Income (in dollars)
mean
median
standard deviation

Less than
one acre
0.79
0.00
1.18
24.30
14.25
18.98
$48,979.70
$42,500.00
$33,109.00
$20,004.90
$18,475.00
$13,262.00
LOT SIZES
I to 9 acres
0.98
0.00
1.26
23.62
14.25
20.30
$59,411.60
$47,500.00
$45,918.80
$20,821.90
$19,220.00
$13,955.90

10 or More
acres
0.77
0.00
1.25
37.24
34.25
22.52
$46,422.80
$37,500.00
$40,781.80
$17,260.10
$14,660.00
$13,487.50
*Numbers are in hundreds.
                                   18

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    MAIN  FEATURES  OF  UNSEWERED  SINGLE  FAMILY  DWELLINGS ON  LOT SIZE

     OF LESS THAN ONE ACRE WHEN CLASSIFIED BY RURAL/URBAN LOCATION

                              1980 CENSUS
     Fifty nine  percent of  all  unsevered  single  family dwellings  on
lot size of less than one acre were located fn rural acres.

     Of these rural unsevered dwellings,  762  were  occupied  year round,
922 had complete plumbing facilities and  42%  received the water supply
from a public system or a private company.

     Of  the  urban  un9ewered dwellings 942 were occupied  year round,
972 had complete plumbing facilities and  782  received the water .supply
from a public system or a private company.

     The median  number  of  bedrooms in  both rural and  urban dwellings
was  three.   Rut  the  median number  of  bathrooms  in  urban dwellings
was  1.5  and  in rural  dwellings  was 1.0.   The  median number  of adult
and  child occupants  in both the  rural  and urban  dwellings  was  the
same.

     The  average  household  income  and the average  property  value  of
urban dwellings was significantly higher than for rural dwellings.
                                    19

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                                TABLE 6




 CHARACTERISTICS OF UNSEWERED SINGLE FAMILY DWELLINGS ON LOT SIZE




          OF LESS THAN ONE ACRE — RURAL/URBAN CLASSIFICATION




                         (SOURCE:   1980  CENSUS)
CHARACTERISTICS OF DWELLINGS
RURAL
URBAN
Total Number of dwellings*
Number of dwellings*
occupied year round
vacant year round
with seasonal occupancy
Number of dwellings with*
complete plumbing
incomplete plumbing
Number of dwellings with
water supply from*
public or private company
other source
Number of bedrooms
mean
median
standard deviation
Number of bathrooms
mean
median
standard deviation
Number of adult occupants
mean
median
standard deviation
Age of adult occupants
mean
median
standard deviation
53,927

61,286
6,361
6,280

49,469
4,458


22,815
31,112

2.61
3.00
0.89

1.22
1.00
0.46

1.56
2.00
1.08

45.30
40.67
16.53
37,237

34,832
1,845
560

36,333
904


29,197
8,040

2.84
3.00
0.85

1.40
1.50
0.46

1.99
2.00
0.94

45.16
41.00
15.40
                                   20
               (continued)

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                              TABLE 6 (continued)
CHARACTERISTICS OF DUELLINGS       RURAL               URBAN
Number of children
mean
median
standard deviation
Age of dwelling (in years)
mean
median
standard deviation
Value of property (in dollars)
mean
median
standard deviation
Household income (in dollars)
mean
median
standard deviation
0.73
0.00
1.17
24.86
14.25
20.37
S43.130.70
837,500.00
$29,594.30
SIR, 211. 30
516,715.00
$12,271.40
0.87
0.00
1.20
23.48
24.25
16.74
S55.658.20
847,500.00
$35,555.70
$22,130.80
$20,705.00
$14,054.70
*Numbers are in hundreds.
                                   21

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     MAIN FEATURES OF UNSEWERER SINGLE FAMILY DWELLINGS ON LOT SIZE

   OF LESSTHAN ONE ACRE WHEN CLASSIFIED BY THE SOURCE OF WATER SUPPLY

                               1980  CENSUS
     The  public water  system  or  a  private  water company  served  57%
of  the  unsewered  single  family  dwellings  on  lot  size of  less  than
one acre.  The remaining dwellings were served by wells,  creeks, springs
or some other  source.

     Of dwellings  served by public water  system or a private company,
90% were  occupied  year  round and 97%  had complete  plumbing facilities.

     Of  dwellings  served  by  other sources  of water  supply,  75%  were
occupied  year  round and 90% had complete plumbing  facilities.

     The  average  value of property  and the  average  household  income
•was  significantly  larger in dwellings  that  received  water  supply  from
a public  system  or a private company  than that  in  the  other category.
                                    22

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                                  TABLE 7

   CHARACTERISTICS OF UNSEWERED SINGLE FAMILY DWELLINGS ON LOT SIZE

 OF LESS THAN ONE ACRE — CLASSIFICATION BY THE SOURCE OF WATER SUPPLY

                           (SOURCE:   1980  CENSUS)
CHARACTERISTICS OF
DWELLINGS
PUBLIC SYSTEM OR
PRIVATE  COMPANY
ALL OTHER SOURCES
Total number of dwellings*
Number of duellings*
occupied year round
vacant year round
with seasonal occupancy
Number of dwellings with*
complete plumbing
incomplete plumbing
Number of bedrooms
mean
median
standard deviation
Number of bathrooms
mean
median
standard deviation
Number of adult occupants
mean
median
standard deviation
Age of adult occupants
mean
median
standard deviation
52,012

46,639
3,633
1,740

50,356
1,656

2.79
3.00
0.85

1.37
1.00
0.47

1.88
2.00
0.98

45.32
41.00
15.86
39,152

29,479
4,573
5,100

35,446
3,706

2.59
3.00
0.91

1.20
1.00
0.46

1.54
2.00
1.10

45.09
40.50
16.26
                                                       (continued)
                                    23

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                            TABLE 7 (continued)
CHARACTERISTICS OP                 PUBLIC SYSTEM OR    ALL OTHER SOURCES
DWELLINGS                          PRIVATE  COMPANY
Number of children
mean
median
standard deviation
Age of dwelling (in years)
mean
median
standard deviation
Value of property (in dollars)
mean
median
standard deviation
Household income (in dollars)
mean
median
standard deviation

0.84
0.00
1.20

23.74
14.25
18.53

$51,263.10
$47,500.00
$34,fl63.80

$20,722.20
$19,205.00
$13,540.30

0.71
0.00
1.15

25.03
24.25
19.54

$45,255.70
$42,500.00
$29,653.50

$18,870.00
$17,315.00
$12,727.40
*Numbers are in hundreds.
                                   24

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     MAIN  FEATURES  OF  UNSEWERED SINGLE  FAMILY DWELLINGS ON LOT SIZE

    OF LESS THAN ONE ACRE WHEN CLASSIFIED BY THE NUMBER OF  BEDROOMS

                               1980 CENSUS
     A classification of single family dwellings was made by the number
of bedrooms  782 of dwellings  had  two or three bedrooms,  152  had  four
or more bedrooms and only 72 of dwellings had no more than one  bedroom.

     Of dwellings  with  no  more  than one  bedroom,  582 were  occupied
year  round,  712 had  complete  plumbing  facilities  and 422  received
water supply from a public system or a private company.

     Of dwellings  with two or  three  bedrooms,  852 were  occupied  year
round,  962  had complete  plumbing  facilities  and  57%  received water
supply from a public system or a private company.

     Of dwellings with four or more bedrooms 90Z had year round occupancy,
982  had  complete  plumbing  facilities and  632  received  water supply
from a public system or a private company.

     The median number of  adult  occupants  in  dwellings with  no  more
than  one  bedroom was  one  as  compared to two In  dwellings  with larger
number of  bedrooms.  The median  number  of children  in dwellings  with
four  or  more  bedrooms was one as  compared to  zero in dwellings  of
smaller sizes.

     The smallest  size dwellings  were found  to be  significantly  older
than  dwellings  of  other sizes.   No significant difference in  the  age
of the other two categories of dwellings was observed.

     The  average age  of adult occupants  was  significantly   smaller
in larger dwellings than that  in smaller dwellings.

     The average property value and  the average household  income  was
significantly larger for larger dwellings.
                                    25

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                                  TABLE 8

     CHARACTERISTICS OF UNSEWERED SINGLE FAMILY DWELLINGS ON LOT

SIZE OF LESS THAN ONE ACRE — CLASSIFICATION BY THE NUMBER OF BEDROOMS

                           (SOURCE:   1980  CENSUS)
Charatercistics of Dwellings
One or less
 Bedrooms
 2 Co 3
Bedrooms
4 or more
Bedrooms
Total number of dwellings*       6,870

Number of dwellings*
   occupied year round           3,959
   vacant year round             1,277
   with seasonal .occupancy       1,634

Number of dwellings with*
   complete plumbing             4,851
   incomplete plumbing           2,019

Number of dwellings with
water supply from*
   public or private company     2,919
   other source                  3,951
              70,819
              60,002
               6,141
               4,676
              67,737
               3,082
              40,547
              30,272
                13,475
                12,157
                   788
                   530
                13,214
                   261
                 8,546
                 4,929
Number of bathrooms
mean
median
standard deviation
Number of adult occupants
mean
median
standard deviation
Age of adult occupants
mean
median
standard deviation

0.88
1.00
0.32

0.90
1.00
0.91

49.72
52.00
20.31

1.28
1.00
0.44

1.72
2.00
0.98

45.56
41.33
16.27

1.62
2.00
0.46

2.20
2.00
1.17

42.17
38.67
12.23
                                                              (continued)
                                   26

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                            TABLE « (continued)
Characercistics of Dwellings
One or less
 Bedrooms
 2 to 3
Bedrooms
4 or more
Bedrooms
Number of children
   mean                               0.19          0.72            1.45
   median                             0.00          0.00            1.00
   standard deviation                 0.69          I.10            1.50

Age of dwelling (in years)
   mean                              30.66         23.73           24.04
   median                            24.25         14.25           14.25
   standard deviation                19.86         18.58           19.97

Value of property
(in dollars)
   mean                         $27,871.70    S45,601.90      369,139.20
   median                       $21,250.00    $42,500.00      S62.500.00
   standard deviation           $25,823.10    $28,645.50      $43,741.00
Household Income (in dollars)
mean
median
standard deviation
$10,850.40
$ 8, 005. 00
$ 9,517.60
$19,275.50
$18,005.00
$12,409.10
$26,586.20
$25,695.00
$15,444.40
*Numbers are in hundreds.
                                   27

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     MAIN FEATURES OF UNSEWERED SINGLE  FAMILY  DWELLINGS ON LOT SIZE

     OF LESS THAN ONE ACRE WHEN CLASSIFIED BY THE ACE OF DWELLINGS

                               1980 CENSUS-
     On  the  basis  of  age  unsewered  dwellings were  classified Into
these  groups.   277.  dwellings  were less  than  10  years  old, 44* were
between 10 and 30 years old and 29* were more than 30 years old.

     Of dwellings  chat  were less than  10 years old,  82* were occupied
year  round,  97*  had complete  plumbing facilities  and   57* received
water  supply from a  public system or a private company.

     Of dwellings  which were  10-30 years  old, 86* were  occupied year
round, 96*  had  complete  plumbing  facilities  and  69*  received  water
supply from a public system or a private company.

     Of  the  30 years  old or  older  dwellings, 81* were  occupied year
round,  89* had complete  plumbing facilities  and 60*  received  water
supply from a public system or a private company.

     The  median  number of bedrooms  was  three for  dwellings younger
Chan thirty years of age and two for older ones.

     The  average  age  of  adult  occupants  was  significantly higher,
in older dwellings than in younger ones.

     The  average  property value and  the average household  income were
significantly higher in younger dwellings compared to the older ones.
                                    28

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                                  TABLE 9

      CHARACTERISTICS OF UNSEWERED SINGLE  FAMILY DWELLINGS ON LOT SIZE

      OF LESS THAN ONE ACRE — CLASSIFICATION BY THE AGE OF DWELLINGS

                           (SOURCE:  1980 CENSUS)
CHARACTERISTICS OF
DWELLINGS
DWELLING-AGE
 <10 YEARS
DWELLING-AGE
10-30 YEARS
DWELLING-AGE
  >30 YEARS
Total number of-dwellings*  24,581
                40,109
                   26,474
Number of dwellings*
occupied year round
vacant year round
with seasonal occupancy
Number of dwellings with*
complete plumbing
incomplete plumbing
Number of dwellings with
water supply from*
public or private
company
other sources
Number of bedrooms
mean
median
standard deviation
Number of bathrooms
mean
median
standard deviation
Number of adult occupants
mean
median
standard deviation

20,155
2,554
1,872

23,886
695



13,987
10,594

2.87
3.00
0.80

1.53
1.50
0.48

1.70
2.00
0.99

34,401
2,767
2,941

38,436
1,673



23,731
16,378

2.72
3.00
0.85

1.30
1.00
0.45

1.83
2.00
1.07

21,562
2,885
2,027

23,480
2,994



14,294
12,180

2.54
2.00
0.96

1.07
1.00
0.38

1.61
2. 00
1.07
                                                           (continued)
                                   29

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                             TABLE  9  (continued)
CHARACTERISTICS OF
DWELLINGS
DWELLING-AGE
 <10 YEARS
DWELLING-AGE
10-30 YEARS
DWELLING-AGE
  >30 YEARS
Age of adult occupants
   mean                          39.63          45.67
   median                        35.50          42.00
   standard deviation            13.44          15.21

Number of children
   mean                           1.00           0.77
   median                         0.00           0.00
   standard deviation             1.23           1.17

Value of property
(in dollars)
   mean                    $59,250.80     $50,207.00
   median                  $52,500.00     $42,500.00
   standard deviation      $34,638.90     $31,672.90
                                      49.78
                                      48.50
                                      17.82
                                       0.60
                                       0.00
                                       1.12
                                 $34,973.40
                                 $28,750.00
                                 $28,730.00
Household income
(in dollars)
mean
median
standar deviation


$22,348.00
$21,110.00
$12,901.10


$21,282.50
$19,820.00
$13,707.60


$15,776.20
$13,380.00
$11,829.50
*Numbers are in hundreds.
                                   30

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     MAIN FEATURES OF UNSEWERED SINGLE FAMILY DWELLINGS ON LOT SIZE

     OF LESS THAN ONE ACRE  WHEN CLASSIFIED BY THE  VALUE OF PROPERTY

                               1980 CENSUS
     On the basis of  property  value,  unsevered  single family dwellings
were classified  into three groups:   (a) dwellings  with property value
<$23,000, (b)  dwellings with property  value between  $25,000 and $50,000,
and (c)  dwellings  with property  value of >S50,000.   21Z  of unsewered
dwellings were in category  (a), 39Z in category (b),  and  40Z in  category
(c).

     Of dwellings in category (a), 91Z had complete plumbing facilities
and 55% received water supply from a public system or a private company.

     Of dwellings in  categories  (b) and  (c),  99Z had complete plumbing
facilities.   Public  water  system  or  a private company  supplied  water
to  622  and 65Z  of  dwellings  in  categories  (b)  and  (c) respectively.
In each category 98Z of dwellings were occupied year round.

     The median  number of  bedrooms was  two  in  category (a) and  three
in  the other  two categories.  The median  number of  bathrooms  was  two
in category (c) as compared to one in  the other two categories.

     The  median number of adult  occupants  was  two  in each  category
but the median number of child occupants was one in category (c) compared
to zero in the other two categories.

     The average age of adult occupants and  the average  age of dwellings
were significantly smaller in more expensive dwellings.  And,  in more
expensive  dwellings,  the  average household  income  was significantly
larger.
                                    31

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                                  TABLE 10

      CHARACTERISTICS OF UNSEWERED SINGLE FAMILY DWELLINGS ON LOT SIZE

      OF LESS THEN ONE ACRE — CLASSIFICATION BY THE VALUE OF PROPERTY*

                           (SOURCE:   1980 CENSUS)
CHARACTERISTICS OF
DWELLINGS
PROPERTY VALUE  PROPERTY VALUE  PROPERTY VALUE
  < $25,000    S25.000-S50.000     > $50,000
Total number of dwellings*
   13,231
24,922
25,324
Number of dwellings*
occupied year round
vacant year round
with seasonal occupancy
Number of dwellings with*
complete plumbing
incomplete plumbing
Number of dwellings with
water supply from*
public or private company
other source
Number of bedrooms
mean
median
standard deviation
Number of bathrooms
mean
median
standard deviation
Number of adult occupants
mean
median
standard deviation

12,926
305
0

12,014
1,217


7,285
5,946

2.44
2.00
0.83

1.03
1.00
0.30

1.94
2.00
0.88

24,533
389
0

24,780
142


15,471
9,451

2.79
3.00
0.71

1.27
1.00
0.40

2.06
2.00
0.81

24,781
543
0

25,260
64


16,594
8,730

3.15
3.00
0.75

1.67
2.00
0.41

2.13
2.00
0.79
                                                              (continued)
                                   32

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                            TABLE 10 (continued)
CHARACTERISTICS OF          PROPERTY VALUE  PROPERTY VALUE  PROPERTY VALUE
DWELLINGS                     < $25,000    $25,000-$50,000     > 850,000
Age of adult occupants
   mean                            51.46         45.39              43.72
   median                          51.50         41.00              39.50
   standard deviation              17.44         15.95              13.63

Number of children
   mean                             0.73          0.90                1.02
   median                           0.00          0.00                1.00
   standard deviation               1.24          1.18                1.21

Age of dwelling (in fears)
   mean                             33.49        23.39              16.64
   median                           24.25        14.25              14.25
   standard deviation               20.18        17.82              14.86
Household income (in dollars)
mean
median
standard deviation
S12.84S.OO
$10,715.00
$ 9,543.40
$19,555.20
$18,815.00
$11,025.20
S26.874.80
$26,010.00
$14,396.10
*Numbers are  in hundreds.

••"Property value is  not  reported  for  vacant  units  except  vacant  for  sale,
 renter occupied  units  or with a commercial establishment or medical
 office on  property.  Hence  the  number  of dwellings  for  which property
 value is available Is  less  than the number of  unsevered dwellings.
                                    33

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SECTION III

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                          TABLE  11




CLASSIFICATION OF STRUCTURES BY TYPE OF SEWAGE IN EACH STATE*




                    (SOURCE:   1970 CENSUS)

STATE /STATE ALL HOUSING UNITS UNSEWERED HOUSING
GROUP STRUCTURES** UNITS

Alabama
Alaska
Arizona
Arkansas
California
Colorado
Connecticut
Delaware
District of
Columbia
Florida
Georgia
Hawaii
Idaho
Illinois
Indiana

12,003
1,129
6,264
7,213
75,735
8,390
10,650
1,975
3,181
26,949
16,077
2,546
2,629
39,828
18,658
TOTAL
11,203
909
5,842
6,758
69,945
7,567
9,802
1,808
2,790
25,265
14,702
2,168
2,449
37,010
17,298
SEWERED
5,684
562
4,450
3,562
60,852
6,118
6,029
1,329
2,774
15,407
8,576
1,600
1,379
30,758
10,668
SEPTIC TANK/ OTHER
UNSEWERED CESS POOL MEANS
5,519
347
1,392
3,196
9,093
1,449
3,773
479
16
9,858
6,126
568
1,070
6,252
6,630
3,917
164
1,204
2,241
8,691
1,227
3,709
426
4
9,430
4,710
530
987
5,606
6,001
1,602
183
188
955
402
222
64
53
12
428
1,416
38
83
646
629
                                                      (continued)
                         34

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TABLE 11 (continued)

STATE/STATE ALL HOUSING UNITS UNSEWERED HOUSING
GROUP STRUCTURES** UNITS
SEPTIC TANK/ OTHER
TOTAL SEWERED UNSEWERED CESS POOL MEANS
Iowa
Kansas
Kentucky
Louisiana
Maine
Maryland
Massachusetts
Michigan
Minnesota
Mississippi
Missouri
Montana
Nebraska
Nevada
New Hampshire
New Jersey
New Mexico
10,553
8,751
11,644
12,496
4,353
13,532
20,950
31,534
13,887
7,571
18,119
2,669
5,676
1.S24
3,111
25,340
3,494
9,641
7,893
10,643
11,505
3,972
12,488
18,890
29,538
12,758
6,997
16,738
2,467
5,150
1,728
2,806
23,875
3,257
6,677
5,970
5,383
7,857
1,752
9,5fl2
13,428
19,598
8,697
3,360
11,759
1,516
3,868
1,476
1,378
19,481
2.325
2,964
1,923
5,260
3,648
2,220
2,906
5,462
9,940
4,061
3,637
4,979
951
1,282
252
1,428
4,394
932
2,588
1,612
3,194
2,837
1,746
2,530
5,371
9,169
3,378
2,122
3,650
810
1,047
229
1,321
4,281
678
376
311
2,066
811
474
376
91
771
683
1,515
1,329
141
235
23
107
113
254
                                 (continued)
     35

-------
TABLE 11 (continued)

STATE/STATE ALL
GROUP STRUCTURES
New York
North Carolina
North Dakota
Ohio
Oklahoma
Oregon
Pennsylvania
Rhode Island
South Carolina
South Dakota
Tennessee
Texas
Utah
Vermont
Virginia
Washington
67,520
18,295
2,318
37,100
10,316
8,003
42,245
3,678
9,194
2,533
13,993
41,370
3,441
1.S54
16,877
13,374
HOUSING UNITS UNSEWERED HOUSING
UNITS
SEPTIC TANK/ OTHER
TOTAL SEVERED UNSEWERED CESS POOL MEANS
62,973
16,410
2,043
34,651
9,400
7,447
39,244
3,163
8,150
2,252
13,003
38,289
3,158
1,653
14,930
12,203
48,456
7,453
1,276
25,740
6,899
4,543
28,011
1,989
3,661
1,422
6,720
29,998
2,595
717
9,075
7,847
14,517
8,957
767
8,911
2,501
2,904
11,233
1,174
4,489
830
6,283
8,291
563
936
5,855
4,356
13,924
6., 974
567
7,816
1,999
2,758
10,125
1,149
3,402
627
4,617
6,617
497
809
4,104
4,150
593
1,983
200
1,095
502
146
1,108
25
1,087
203
1,666
1,674
66
127
1,751
206
                                 (continued)
     36

-------
                               TABLE 11  (continued)
STATE/STATE      ALL
   GROUP     STRUCTURES'
HOUSING UNITS
                          TOTAL
   SEVERED
         UNSEWERED HOUSING
               UNITS

          SEPTIC TANK/ OTHER
UNSEWERED  CESS POOL   MEANS
West Virginia
Wisconsin
Wyoming
6,361
16,058
1,250
5,971
14,718
1.162
3,041
9,986
871
2,930
4,732
291
1,881
4,092
253
1,049
640
38
 ^Numbers are in hundreds.

**The numbers indicated under all structures include group quarters.  All
  group quarters are severed.
                                   37

-------
                          TABLE 12




CLASSIFICATION OF POPULATION BY TYPE OF SEWAGE IN EACH STATE*




                   (SOURCE:  1970 CENSUS)

STATE
Alabama
Alaska
Arizona
Arkansas
California
Colorado
Connecticut
Delaware
District of
Columbia
Florida
Georgia
Hawaii
Idaho
Illinois
Indiana
TOTAL
33,719
2,768
17,243
18,796
193,451
21,263
29,405
5,326
7,141
66,086
44,567
7,305
6,945
107,986
50,502
POPULATION UNSEWERED POPULATION SERVED
BY BY
SEPTIC TANK/ OTHER
SEWERED UNSEWESED CESS POOL MEANS
16,497
1,703
13,156
9,548
168,395
17,574
17,135
4,011
7,075
37,748
25,032
5,312
3,827
88,927
30,146
17,222
1,065
4,087
9,248
25,056
3,689
12,270
1,315
66
28,338
19,535
1,993
3,118
19,059
20,356
12,009
606
3,426
6,555
24,436
3,413
12,140
1,148
15
27,035
14,767
1,389
3,020
17,794
18,985
5,213
459
661
2,693
620
276
130
167
51
1,303
4,768
104
98
1,265
1,371
                                                     (continued)
                           38

-------
TABLE 12 (concinued)

STATE
Kansas
Kentucky
Louisiana
Maine
Maryland
Massachusetts
Michigan
Minnesota
Mississippi
Missouri
Montana
Nebraska
Nevada
New Hampshire
New Jersey
New Mexico
New York
North Carolina
TOTAL
21,550
31,205
35,360
9,519
38,043
54,655
86,721
36,925
21,622
45,370
6,728
14,343
4,790
7,095
70,198
9,916
177,567
48,809
POPULATION (JNSEWERED POPULATION SERVED
BY BY
SEPTIC TANK/ OTHER
SEVERED UNSEVERED CESS POOL MEANS
16,140
15,015
23,563
4,754
28,817
37,944
58,754
25,379
9,800
32,023
4,073
10,631
4,111
3,797
56,709
7,019
132,895
21.128
5,410
16,190
11,797
4,765
9,226
16,711
27,967
11,546
11,822
13,347
2,655
3,712
679
3,298
13,489
2,897
44,672
27,681
4,846
10,050
9,254
4,229
8,067
16,550
27,158
10,758
6, 597
10,476
2,477
3,219
631
3,170
13,217
2,189
43,658
21,240
564
6,140
2,543
536
1,159
161
809
788
5,225
2,871
178
493
48
128
272
708
1,014
6,441
       39
                               (continued)

-------
                               TABLE 12 (continued)

STATE
North Dakota
Ohio
Oklahoma
Oregon
Pennsylvania
Rhode Island
South Carolina
South Dakota
Tennessee
Texas
Utah
Vermont
Virginia
Washington
West Virginia
Wisconsin
Wyoming
TOTAL
5,913
103,993
24,625
20,320
114.H07
8,948
24,795
6,406
38,262
108,620
10,330
4,284
44,479
32,899
17,053
42,733
3,226
POPULATION UNSEWERED POPULATION SERVED
BY BY
SEPTIC TANK/ OTHER
SEWERED UNSEWERED CESS POOL MEANS
3,650
74,884
17,737
11,733
80,533
5,378
10,421
3,958
19,072
86,550
8,575
2,0:i
26, 1""
20,1 "I
8,IM
29,386
2,400
2,263
29,109
6,868
8,587
34,274
3,570
14,374
2,448
19,190
22,070
1,755
2,263
18,090
12,718
8,902
13,347
826
1.97
26,341
5,696
8,430
31,971
3,534
10,541
2,058
14,350
17,890
1,661
2,072
12,795
12,539
5,882
12,573
775
288
2,768
1,192
157
2,303
36
3,833
390
4,840
4,180
94
191
5,295
179
3,020
774
51
*Nuabers are in hundreds.
                                   40

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           MAIN FEATURES  OF UNSEWERED  SINGLE  FAMILY DWELLINGS

                              1970 CENSUS
     According  Co  Che  1970  census,  Che  number of  unsevered single
family  dwellings  was  approximately  18 million.   Of these  dwellings
87%  were  occupied  year round,  80* had complete  plumbing facilities
and 37Z received water supply from a public system or a private company.

     The median  number of  rooms and bathrooms  was  respectively  five
and one.  The median number of adult and  child occupants was respectively
two and zero.

     The average age  of adult occupant was 46.4 years and  the average
age  of  property was  27.8  years.   The  average value  of property  was
318,543 and the average family income was $9,299 per annum.

-------
                                TABLE 13

     CHARACTERISTICS OF THE UNSEWERED SINGLE FAMILY DWELLINGS

                         (SOURCE:  1970 CENSUS)




CHARACTERISTICS OF DWELLINGS


Total number of dwellings*              181,242

Number of dwellings*
   occupied year round                  157,296
   vacant or with seasonal
     occupancy                           23,946

Number of dwellings with*
   complete plumbing                    145,502
   incomplete plumbing                   35,740

Number od dwellings with water
supply from*
   public or private company             67,419
   other source                         113,823

Number of rooms
   mean                                       5.44
   median                                     5.00
   standard deviation                         1.60

Number of bathrooms
   mean                                       1.13
   median                                     l.QO
   standard deviation                         0.53

Number of adult occupants
   mean                                       1.85
   median                                     2.00
   standard deviation                         1.01

Age of adult occupants
   mean                                      46.41
   median                                    43.66
   standard deviation                        15.41


                               42                    (continued)

-------
                          TABLE 13  (continued)
CHARACTERISTICS OF DWELLINGS
Number of children
   mean                                       1.17
   median                                     0.00
   standard deviation                         1.64

Age of dwelling (in years)
   mean                                      27.76
   median                                    25.00
   standard deviation                        18.78

Value of property (in dollars)
   mean                                 $18,543.20
   median                               816,250.00
   standard deviation                   $12,915.60

Family income (in dollars)
   mean                                  $9,299.40
   median                                $8,050.00
   standard deviation                    $7,856.04
*Numbers are in hundreds
                              43

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               MAIN FEATURES  OF1 SINGLE FAMILY DWELLINGS

             WHEN CLASSIFIED BY THE SOURCE OF WATER SUPPLY

                              1970 CENSUS
     Thirty-seven  percent  of dwellings  received water supply from
a  public  system or  a  private  company.   Of these  90Z were  occupied
year round and 89Z had complete plumbing  facilities.

     Of dwellings  for which  the source of water  supply  was  other  than
Che public water system  or a private  company,  851 were occupied  year
round and 75!! had complete plumbing facilities.

     The  occupants of dwellings  that received  water  supply  from  a
public system or a  private  company were  significantly younger  than
the occupants of other dwellings.

     The  average value  of  property and  the average household  Income
was significantly  larger  in  dwellings  that received water supply  from
a public system or a private company than that in the other category.

-------
                                  TABLE 14

          CHARACTERISTICS OF UNSEWERED SINGLE FAMILY DWELLINGS —

                CLASSIFICATION BY THE SOURCE OF  WATER SUPPLY

                           (SOURCE:   1970 CENSUS)
CHARACTERISTICS OF
DWELLINGS
PUBLIC SYSTEM OR
PRIVATE COMPANY
ALL OTHER
 SOURCES
Total number of dwellings*

Number of dwellings*
   occupied year round
   vacant or with seasonal
     occupancy

Number of dwellings wich*
   complete plumbing
   incomplete plumbing
   67,419
   60,745
    6,674
   60,372
    7,047
 113,823
  96,351
  17,272
  85,130
  28,693
Number of rooms
mean
median
standard deviation
Number of bathrooms
mean
median
standard deviation
Number of adult occupants
mean
median
standard deviation
Age of adult occupants
mean
median
standard deviation

5.54
5.00
1.56

1.27
1.00
0.57

1.91
2.00
0.94

45.71
42.67
15.18

5.39
5.00
1.63

1.05
1.00
0.49

1.81
2.00
1.04

46.85
44.50
15.53
                                                           (continued)
                                   45

-------
                            TABLE 14  (continued)
CHARACTERISTICS OF                PUBLIC SYSTEM OR        ALL OTHER
DWELLINGS                         PRIVATE COMPANY          SOURCES
Number of children
mean
median
standard deviation
Age of dwelling (in years)
mean
median
standard deviation
Value of property (in dollars)
mean
median
standard deviation
Family income (in dollars)
mean
median
standard deviation
1.20
0.00
1.58
23.89
15.00
17.77
$20,239.70
$18,750.00
$13,222.30
$10,619.50
$ 9,250.00
$ 8,512.61
1.15
0.00
1.68
30.05
25.00
18.99
$16,771.80
$12.341.00
$12,332.60
$8,468.80
$7,150.00
$7,291.79
*Numbers are in hundreds.

-------
           MAIN FEATUES OF UNSEWERED SINGLE FAMILY DWELLINGS

                WHEN CLASSIFIED BY  THE  NUMBER OF  ROOMS

                              1970 CENSUS
     Unsewered  dwellings  were  classified inCo the  following these
groups  ~  (a)  dwellings  with  less  than three  rooms,  fb)  dwellings
with between  three and six rooms, (c)  dwellings with  more than  six
rooms.  Category  (b)  was  most popular with  74Z of  dwellings  belonging
Co  this  group.   23Z  of  dwellings  belonged  to category  (c) and  only
3Z to category  (a).

     Of dwellings in  category  (a), 52Z  were occupied year  round,  26Z
had  complete  plumbing facilities  and  28Z received  water supply  from
a public system or a private company!

     Of dwellings in  category  (b), 865!  were occupied year  round,  79Z
had  complete  plumbing facilities  and  only  372  received water  supply
from a public system or a private company.

     Of dwellings in  category  (c), 94Z  were occupied year round,  93Z
had  complete  plumbing facilities  and 39Z  received water supply  from
a public system or a private company.

     The  small  dwelling  units were  occupied  by  significantly  older
occupants.

     The  dwellings  in category  (c) were significantly older than  the
other units.   In the other  two categories,  ao significant  difference
In the average age of dwelling was observed.

     The  average property  value and  the  average  family income  was
significantly larger for larger dwellings.

-------
                                  TABLE 15

          CHARACTERISTICS OF UNSEWERED SINGLE FAMILY DWELLINGS —

                   CLASSIFICATION BY THE NUMBER OF ROOMS

                           (SOURCE:   1970 CENSUS)
Characteristics of
Dwellings
Less than
 3 Rooms
3 to 6
Rooms
More than
 6 Rooms
Total number of dwellings*     5,476

Number of dwellings*
   occupied year round         2,855
   vacant or with seasonal     2,621
     occupancy

Number of dwellings with*
   complete plumbing           1,445
   incomplete plumbing         4,031

Number of dwellings with
water supply from*
   public or private company   1,533
   other source                3,943
               134,076
               115,487
                18,589
               105,386
                28,690
                49,700
                84,376
                  41,690
                  39,188
                   2,502
                  38,671
                   3,019
                  16,186
                  25,504
Number of bathrooms
mean
median
standard deviation
Number of adult occupants
mean
median
standard deviation
Age of adult occupants
mean
median
standard deviation

0.66
0.50
0.29

0.75
0.00
0.94

51.59
53.75
18.72

1.04
1.00
0.42

1.80
2.00
0.99

46.84
44.50
15.82

1.51
1.00
0.67

2.14
2.00
0.94

44.82
41.50
13.66
                                                              (continued)
                                   48

-------
                               TABLE IS  (continued)

Characteristics of
Dwellings
Number of children
mean
median
standard deviation
Age of dwelling (in years)
mean
median
standard deviation
Value of property (in
dollars)
mean
median
standard deviation
Family income (in dollars)
mean
median
standard deviation
Less than
3 Rooms

0.35
0.00
1.27

26.43
25.00
18.31


$7,292.20
$3,500.00
$6,885.50

$3,782.30
$2,250.00
$4,317.40
3 to 6
Rooms

1.05
0.00
1.56

27.17
25.00
18.39


$15,391.70
$13,750.00
$ 9,902.50

$8,133.30
$7,250.00
$6,333.40
More than
6 Rooms

1.66
1.00
1.82

29.84
25.00
19.91


328,169.70
$30,000.00
$15,663.10

$13,104.80
$11,050.00
$10,380.10
*Numbers are in hundreds.
                                  49

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          MAIN FEATURES  OF UNSEWERED  SINGLE  FAMILY  DWELLINGS

                WHEN CLASSIFIED BY THE AGE OF DWELLINGS

                              1970 CENSUS
     On  che  basis of  their age,  unsewered  dwellings were  classified
Into  the following  three  groups  —  (a)  less  than  ten years  of  age,
(b) between  ten  and thirty  years of  age,  and  (c)  more than thirty
years of age.   Only  252 of  dwellings  belonged to category  (a).   The
remaining dwellings were more or  less  equally divided between categories
(b) and  (c) with 36Z  belonging to  the  farmer  and  392  belonging  to
the latter.

     Of  dwellings  in category (a), 852 were occupied year  round,  88Z
had complete  plumbing  facilities  and 43Z received  water supply  from
a public system or a private company.

     Of  dwellings  in category (b), 872 were occupied year  round,  832
had complete  plumbing  facilities  and 43% received  water supply  from
a public system or a private company.

     Of  dwellings  in category (c), 872 were occupied year  round,  732
had  complete  plumbing  facilities  and  282  received water supply  from
a public system or a private company.

     The  median number  of bathrooms  was the  sane  regardless  of  the
age of  a dwelling,  but  the median number of  rooms was six  in houses
more than  thirty  year  of age as  compared to the median number of rooms
of five  in the other two categories.

     The  average age  of  adult  occupants was  significantly  higher  in
older dwellings than in younger  ones.

     The average  property value  and  the  average family  income  were
significantly  higher  in  younger  dwellings  as compared  to  the  older
ones.
                                    50

-------
                       TABLE  16

CHARACTERISTICS OF UNSEWERED SINGLE FAMILY DWELLINGS —

         CLASSIFICATION BY THE AGE OF DUELLING

                 (SOURCE:   1970 CENSUS)
Characteristics of
Dwellings
                      Dwelling Age
                        <10 Years
Dwelling Age
10-30 years
                                                             Dwelling Age
Total number of dwellings*        44,559

Number of dwellings*
   occupied year round            38,034
   vacant or with seasonal         6,525
    occupancy

Number of dwellings with*
   complete plumbing              39,211
   incomplete plumbing             5,348

Number of dwellings with water
supply from*
   public or private company      19,302
   other source                   25,257
                                      65,780
                                      57,535
                                       8.245
                                      54,701
                                      11,079
                                       28,580
                                       37,200
                70,903
                61,727
                 9,176
                51,590
                19,313
                19,537
                51,366
Number of rooms
mean
median
standard deviation
Number of bathrooms
mean
median
standard deviation
Number of adult occupants
mean
median
standard deviation

5.57
5.00
1.61

1.40
1.00
0.62

1.82
2.00
0.95

5.19
5.00
1.46

1.13
1.00
0.49

1.87
2.00
1.00

5.60
6.00
1.69

0.97
1.00
0.43

1.84
2.00
1.04
                                                      (continued)
                         51

-------
                            TABLE  16  (continued)

Characteristics of
Dwellings
Age of adult occupants
mean
median
standard deviation
Number of children
mean
median
standard deviation
Value of property
(in dollars)
mean
median
standard deviation
Family Income (in dollars)
mean
median
standard deviation
Dwelling Age
<10 Years

41.06
38.00
13.05

1.41
1.00
1.61


$23,532.10
$22,500.00
$13,443.80

$11,473.00
$10,150.00
$ 8,320.76
Dwelling Age
10-30 years

45.90
43.67
14.68

1.14
0.00
1.46


$18,330.00
$16,250.00
$12,159.60

$9,752.30
$8,450.00
$7,954.36
Dwelling Age
>30 years

50.18
49.50
16.33

1.05
0.00
1.69


$12,988.50
$11,250.00
$10, 115.30

$7,538.00
$6,050.00
$7,030.90
*Numbers are in hundreds.
                                    52

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                MAIN FEATURES  OF SINGLE  FAMILY  DWELLINGS

                WHEN CLASSIFIED BY  THE VALUE  OF PROPERTY

                               1970 CENSUS
     On che basis of property  value, unsewered dwellings were classified
into the  following three groups  — (a) with property  value  less  than
$25,000,  (b)  with  property  value  between  $25,000  and $50,000,   and
Cc) with  property value greater  than  $50,000.   41* of  dwellings  were
in group (a), 10Z in group (b) and 49Z in group (c).

     Of  dwellings in  group  (a),  992  were occupied  year round,  90Z
had complete  plumbing  facilities  and  48Z  received  water  supply  from
a public system or a private company.

     Of  dwellings in  group  (b),  99Z  were occupied  year round,  99Z
had complete  plumbing  facilities  and  60%  received  water  supply  from
a public system or a private company.

     Of  dwellings in  group  (c),  75*  were occupied  year round,  692
had complete  plumbing  facilities  and  232  received  water  supply  from
a public system or a private company.

     The median number  of rooms and bathrooms were  greater in category
(b) than in the other two categories.

     The  median  number of adult  occupants was  the same  in all  the
three  categories.   The median number  of child  occupants  were one  in
categories (a) and (b) and zero is category (c).

     In category  (c),  the average age  of  dwelling was significantly
greater than in the  other two categories and  the average family  income
was significantly smaller.
                                    53

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                                    TABLE 17

            CHARACTERISTICS OF ITNSEWERED SINGLE FAMILY DWELLINGS —

                    CLASSIFICATION BY THE VALUE OF PROPERTY

                             (SOURCE:   1970 CENSUS)
Characteristics of
Dwellings
Property Value  Property Value  Property Value
   S50,000
Total number of dwellings*

Number of dwellings*
                               73,497
                   18,000
89,745
occupied year round
vacant or with seasonal
occupancy
Number of dwellings with*
complete plumbing
incomplete plumbing
Number of dwellings with water
supply from*
public or private company
other source
Number of rooms
mean
median
standard deviation
Number of bathrooms
mean
median
standard deviation
Number of adult occupants
mean
median
standard deviation
72,458
1,039


65,825
7,672


35,643
37,854

5.36
5.00
1.28

1.11
1.00
0.40

2.08
2.00
0.77
17,809
191


17,904
96


10,770
7,230

6.68
7.00
1.30

1.76
2.00
0.57

2.19
2.00
0.71
67,029
22,716


61,773
27,972


21,006
68,739

5.27
5.00
1.77

1.03
1.00
0.53

1.58
2.00
1.15
                                                              (continued)
                                    54

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                              TABLE 17  (continued)
Characteristics of
Duellings
Property Value  Property Value  Property Value
   <$25,000     $25,000-550,000    >$50,000
Age of adult occupants
mean
median
starvUril ileviation
Number of children
mean
median
standard deviation
Ape of dwelling (in years)
mean
median
standard deviation
Family income (in dollars)
mean
median
standard deviation

47.01
44.00
15.47

1.26
1.00
1.62

24.99
15.00
17.91

$8,626.60
$8,150.00
$5,833.53

43.71
41.00
12.37

1.53
1.00
1.56

14.82
8.00
13.97

$15,511.40
$14,150.00
$ 9,017.01

46.48
44.33
15.08

1.03
0.00
1.66

32.62
50.00
18.63
•
$8,376.10
$6,350.00
$8,651.60
^Numbers are in hundreds.
                                    55

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                               APPENDIX A

                   A METHODOLOGY  TO EXTRAPOLATE  INCOME


Aggregates,  means  and  per capita  figues  are  frequently  required  for
income.   Unfortunately,  no  single  vlaue  is  considered  adequate  for
use  as the mean  of the "$75,000 ore more"   intervals,  since that  can
be  expected to  vary considerably  from  population to population.   The
"pareto method" is however, available for making a reasonable approximation
for  the mean  of the open-ended income interval,  using the  following
formula:
 Where  V » -—•
            b-a
X • The estimated mean  in  the open-end interval.

X • Lower limit of open-end interval  (e.g., $75,000)

a - Logarithm of lower  limit of interval preceding open-end (e.g.,
    the logarithm of $50,000).

b - Logarithm of lower  limit of open-end Interval (e.g., the logarithm
    of $75,000).

c - Logarithm of the sum of the frequencies in the open-end interval
    and the one preceding  it (e.g., the number of cases with income
    $50,000+).

d - Logarithm of the frequency In the open-end Interval (e.g., the
    number of cases with income $75,0004-).
This method  of estimating the  mean for the upper ranges  of  an income
distribution is based largely on the empirical observations of Vllfredo
Pareto in  the  late 1800s.  While studying  income  tax data for various
                                   56

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European countries, he found thac the upper ranges of the Income distribu-
tion could be described by a curve of the general type,  Y • AX~V, where
X is the income size and Y is  the number of  persons having that income
or larger.  The logarithmic form of the curve (Log Y - Log A - V Log X)
is a  straight line.   That  is  if  the logarithms  of  the  income  sizes
are charted  on  a horizontal  scale and the logarithms of  the number
of persons having an income of  a  particular  size  or larger are charted
on  a  vertical  scale,  the  resulting  points will  fall  on  a  straight
line.

Where the  shape  of the  curve  suggests that the  pareto  curve  does  not
apply, espeically  where  the  frequency of the open-end  interval equals
or  exceeds  those  in  the adjacent  interval, it  may be  preferable  to
use an  intuitively reasonable estimate of  the  mean  or  an estimate
derived  from a  similar or  larger  population,  rather  than to  use  an
unreasonable Pareto estimate.

Tor  the  open-ended interval  of  $75,000 or more  on  income  items  on
1980  census  public-use  mlcrodata samples,   the  user should probably
assume that  the  mean  of that  interval is between $90,000 and $150,000
for most  populations,  and  should  reject  a Pareto estimate  outside
of this range.
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                               APPENDIX B

               SIGNIFICANCE TEST FOR DIFFERENCES OF MEANS
     In order to  test  the  significance  of the difference of two sample
means  a  t-test  is  used.   This test assumes that  KI,  X2  ....  Xn
and YI, ?2  •  •  •  •  *m denote, respectively, independent random samples
from the two independent distributors having, respectively, the probability
density  functions n(ult  Q-2  )  an O"2 ).   If  X,  Y, Si,  and  82
denote respectively the two samples means and standard deviations, then
                         (X-Y) - (Ul - u,)
                 t           •••^^•i
                                       U/n + 1/m)
where the random  variable  t  has  a t distribution with a + m -2 degrees
of  freedom.   This  distribution  converges  to a  normal  distribution
for n, m  >  30.  Since in  our  analysis,  sample size was always greater
than 30,  the random variable  was assumed to  be  normally distributed.
All tests were made at the 5Z  level of significance.
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                                GLOSSARY
 ADULT  OCCUPANT:   Any person  18 years  or more  of  age  from  birch  to.
 April  1,  of the relevant census year.

 AGE:   Age at last birthday, i.e., number of completed years from birth
 co April  1,  of  Che  relevant  census  year.   This item was  asked on  a
 complete  count  basis.

 BATHROOMS.  The  presence of bathroom  facilities,  ascertained for all
 occupied  and vacant housing units.   This question was asked on a  sample
 basis.

 Complete   bathroom.   A  room vlch a  flush toilet,  bathtub  or shower,
 and vash  basin with piped hoc  and  cold water  for  the  excluse use  of
'the occupants  of the housing unit.   The equipment  must be Inside the
 unit  being enumerated.

 No bathroom or  only a half bathroom.   A unit wlch no bathroom facilities,
 only  a half  bathroom, or  bathroom  facilicies which are  also for the
 use of  Che  occupants  of  other housing  units.  A half  bathroom has
 at lease  a  flush toilet or a bathtub  or  shower for exclusive use but
 not all Che facilicies for a complete bathroom.
 BEDROOMS.  The number of bedrooms, ascertained for occupied and  vacant
 unics.   Bedrooms  are  rooms  used mainly  for sleeping,  even if  also
 used for  other purposes.  Rooms  reserved for sleeping  such as  guest
 rooms,  even  though  used  infrequently,  are counted  as  bedrooms.   On
 the other  hand, rooms  used  mainly  for other purposes,  even  chough
 used also  for sleeping, such as a  living room wlch  a  -sofa bed,  are
 not considered bedrooms.   A  housing  unlc consisting of only  one  room,
 such as a  one-room efficiency apartment,  is  classified,  by  definition,
 as having no bedroom.  This iCem was  asked on a sample basis.

 CHILD.   Any  person  less Chan 18  years of age from  birch Co April 1,
 of che  relevant census year.

 DWELLINGS.  This category of single family detached housing unit excludes
 group quarters, businesses mobile homes, trailers, boacs, Cents,  vans,
 ecc.  The unics under Chls category can be occupied or vacant.

 DWELLINGS, AGE  OP:   The age of  dwelling* is computed  from Che  year
 che  structure  was  built  until March  1980  for  1980  census data  and
 uncil che  end of 1970 for 1970  census data.  The year  Che  scructurea
 were built is che year  che  original  conscruction of  che building was
 completed.
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FAMILY  INCOME.  Total  income by  several Income  Intervals  and median
income of (primary) families, primary individuals, and household heads,
are  shown  in some housing census  tabulations.   For  the open interval,
income  greater than  $50,000 income  is  taken  to be  $60,000.   Family
income is shown for only 1970 census.

GROUP QUARTERS:  Group quarters  are living arrangements, such as nursing
homes or rooming houses, which are not housing units.

HOUSEHOLD:  .The person or persons occupying a housing unit.

HOUSEHOLD  INCOME  IN  1979:   Total money  income received  in  calendar
year  1979  by all  household  members 15  years  old and  over,  tabulated
for  all households.  .Household  income  differs  from family  income by
including  income  received by  (a)  all  household members 15 years  old
or over,  not just  those  related  to the householder,  and by (b) persons
living  alone and  in  other  nonfamily households.   In  income  tables
for households, the lovest income group (e.g.  less than $2,500) includes
households  that  were classified as having no  1979  Income  as  defined
in the census.  Many of these were living on income "in kind," savings,
or gifts;  were newly created households;  or were households  in which
the sole breadwinner had recently died or left the household. 'However,
many of  the housholds who reported  no income probably had  some money
income  which was  not  recorded in the  census.  Household income  is
reported  on public-use  microdata  in  $10 intervals up  to  $75,000  or
down to a net loss of $9,990 or more.

Median and  mean  household Income figures are based  on all households,
unlike  mean  or  median  income  figures  for  persons 15  years  old  and
over, which exclude persons with no income.

Average household income  is computed only for year  round  occupied
dwelling.  Pareto  approximation we  used to estimate  the average Income
in the  open interval, income greater than $75,000.   (For  details  see
Appendix A).

In 1970  census,   the  data on household  income  was  not  collected  for
all households.  The availability is limited to the sixth count summary
tape.  Hence  the  household income  is not reported  in  the  statistical
abstract for 1970 census.  The total income of family of primary individual
is reported instead.

HOUSING  UNIT.  A  house,  apartment,  mobile home or  trailer, group  of
rooms,  or  single  room  occupied  as  a separate  living  quarter  or,  if
vacant,  intended for  occupancy as  a separate  living  quarter.  Separate
living quarters are those In  which  the occupants  live and eat separately
from any  other persons in the  building which have  direct  access  from
the outside of the building or through a common hall.


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The  occupants may  be a  single  family, one  person living alone,  tvo
or more  families living  together,  or  any  other group  of related  or
unrelated  persons  who  share  living  arrangements.   For vacant  units,
the  criteria of  separateness  and  direct  access are  applied  to  the
intended  occupants  whenever  possible.   If  that   information  cannot
be obtained, the criteria are applied to the previous occupants.

Doth  occupied and  vacant housing-  units  are  included  in the housing
unit inventory, except that recreational vehicles, boats, caves,  tents,
railroad  cars,  and  the  like are  included only  if they  are  occupied
as someone's usual place of residence.  Vacant mobile homes are included
provided they are intended  for occupancy on the  site where they  stand.
Vacant mobile homes  on  dealers' sales  lots, at the factory,  or  in
storage  yards  are excluded from Che housing  inventory.   Housing  unit
status was determined on a completecount basis.
OCCUPANCY  STATUS.   The classification of  all  housing units as  either
occupied  or  vacant.   This  item was  determined on  a complete-count
basis.

Occupied.  The classification of a  housing  unit with a person or persons
living  in It as a  usual  residence when enumerated—or only  temporlly
absent,  for  example,  on  vacation.   A  household consists  of  all  the
persons  who  occupy  a  housing  unit.   If  all  the persons  staying  in
the  unit have their usual  place  of  residence  elsewhere,  the unit  is
classified as vacant.  Complete count figures on housholds  and  occupied
housing  units  should matchalthough sample  estimates  of  households
and occupied housing units may differ because of weighting.

Vacant.  A housing unit with no one living  in it at the time of  enumera-
tion,  unless its occupants  are only temporily absent.   If,  at the
time of enumeration, the unit is temporarily occupied solely by persons
who have  a usual residence elsewhere, it is  also  classified  as vacant.

The housing Inventory includes vacant mobile homes or trailers  intended
to  be  occupied on  the site  where  they  stand.  Vacant mobile  homes
on  dealer sales lots  or  in storage  yards are  not counted as  housing
units.

New units  not yet occupied  are  classified as  vacant  housing  units
if  construction  has reached  a  point where all  exterior  windows  and
doors  are  installed  and final usable  floors  are  in place.   Vacant
units  are excluded  If open to the  elements;  that  is, if the  roof,
walls, windows,  or doors no longer protect the interior from the elements,
or  if  there  is positive  evidence  (such  as sign  on the  house  or  in
the  block)  that the unit is to be  demolished  or is condemned.   Also
excluded  are quarters  being used entirely  for nonresidential  purposes,
such  as  a store  or an  office, or  quarters used for  the storage  of
business  supplied or Inventory, machinery,  or agricultural  products.

                                    61

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Vacant  seasonal  and  migratory  units.  Vacant  units used or  intended
for use  only  in  certain seasons.  Any  unit used throughout  the  year,
even  if  only  occasionally, is excluded.  Seasonal  units  include  those
used  for summer  or winter sports  or  recretion—beach  cottages  and
hunting  cabins, for  example.  Seasonal  units  may also include quarters
for such workers  as herders and  loggers.   Migratory units  include
those for farm workers during crop season.

PERSONS  IN  HOUSEHOLD:  The  number of  persons  living  in Che  housing
unit.   All occupants are counted—not just  those related  to  the house-
holder,  but  also  any  lodgers,  roomers,  boarders,  partners,  wards,
foster children,  and resident  employees  who  share the living  quarters.

PLUMBING FACILITIES:  Presence of toilet facilities, bathing facilities,
and piped  water,  ascertained  for occupied and vacant housing units.
This item was asked on a complete-count  basis.

     1. Complete plumbing for exclusive use.  Piped hot and cold water,
        a flush  toilet, and  bathtub or  shower  for  exclusive use  by
        household members.  All facilities must be in the living quarters,
        but need not  be in the same room.  Rot water need  not be available
        continuously.   A  privy or  chemical toilet  is not counted  as
        a flush  toilet.  A bathtub  or shower  is  counted  only if  it
        is connected to piped running water.
           •
     2. Lacking complete plumbing for exclusive use:  Complete plumbing
        facilities, but also used by another household.  All  facilities
        present,  but with  some  or all of the plumbing  facilities  also
        regularly used by someone who is not a member of the  household.
        This  category  also applied if  the  future  occupants of living
        quarters now vacant would be expected to share the facilities.

     3. Some  but  not  all plumbing  facilities.   Units  with none  or
        two but  not all  three  of these:   hot  and cold piped water,
        flush toilet, and bathtub or shower.

     4. No plumbing facilities.

In  the  statistical abstract completes  plumbing  facilities are  defined
as 1 and 2 and Incomplete plumbing facilities as 3 and 4.
POPULATION:  The number of inhabitants of an area.

ROOMS:  This  category is used  for 1970  census  data since  the  number
of bedroom is not reported for ISZ 1970 sample.

The categories were 1 to 9 or more In 1970.   Respondents  were to count
only whole rooms used for living purposes, such as living rooms,  dining
rooms,  kitchens,  bedrooms,  finished  recreation  rooms,  etc.:   and  to

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 exclude  kitchenettes,  strip  or pullman  kitchens,  bathrooms,  porches,
 balconies,  fovers,  hall, half-rooms, utility  rooms,  unfinished attics
 or  basments, or other space used for storage.

 SEWAGE DISPOSAL:  The type  of sewage disposal system for the structure
 in  which  the  unit  is  located,  ascertained  for occupied  and vacant
 housing units.  This  item was asked on a  sample basis.

 Public sewer.  Connected to a city,  county,, sanitary district, neighbor-
 hood,  or subdivision sewer system.   A  public  sewer may  be  operated
 by a government body or by a  private organization.  Small sewage treatment
 plants,  called "neighborhood  septic tanks"  in some  localities,  are
 classified  as  public sewers.   All  units  in  structures  with  five or
 more units are assumed to be connected to a public sever.

 Septic tank  or cesspool.  An undergroud  tank  or  pit  into which sewage
 flows from the plumbing  fixtures in the building.

 Other means.   Includes  an  individual  sewer  line  running to a creek,
 lake, swamp, etc.; units with a privy;  and other arrangements.

 Unsewered housing  units are  defined  as the  units  served by  septic
 tank, cesspool or other means.

 STRUCTURES:  Structures are  defined to  include  group quarters  along
 with housing units.

 URBAN  AND  RURAL.   Urban and  rural are  type-of-area concepts  rather
 than specific areas outlined on maps.  As defined by the Census  Bureau,
 the  urban  population  comprises all persons living in urbanized  areas
 (UA's) and in places  of 2,500 or more inhabitants outside UA's.

 The  rural  population consists  of  everyone else.   Therefore,   a  rural
 classification need  not  imply  farm residence or a  sparsely   settled
 area, since  a  small  city or town  is  rural  as  long  as it  is  outside
 a UA and has fewer than 2,500 inhabitants.

The  terms  urban and  rural are  independent  of  metropolitan and  non-
 metropolitan designations;  both urban  and rural  areas  occur  inside
 and outisde SMSA's.
VALUE OF THE PROPERTY:  For owner-occupied housing units, the respondent's
estimate  of  the  current  dollar worth  of  the  property.   For vacant
units, value is the price asked for the property.  A property is defined
as the  house  and  land on  which it stands.  Respondents  estimated  the
value of  house and  land even  if  they only owned  the house  or  owned
the property jointly.
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Statistics  on value are  shown  only  for owner-occupied  condominium
units and for "specified owner-occupied" units, i.e.,  one-family houses
on  less  Chan  10  acres and  with  no business  on the property.   Value
tabulations  exclude  renter-occupied units, mobile  homes or  trailers,
houses on  10  or  more acres,  houses with  a  commercial  establishment
or medical office on the property, and noncondominium units in multi-family
buildings (e.g., cooperatives).

When value  data are   presented  solely  for vacant units  for sale only,
the  term "sale price asked"  is  substituted.   In  the  computation  of
aggregate and mean value,  $7,500 is taken  as the average of the interval
"less than $10,000," and $250,000 is taken  as the average of the interval
"$200,000 or more."    This  it en was asked on a  complete-count  basis.
Values for 1980 reflect increased  housing  prices:  the highest category
in 1970 was $50,000 or more," for  1980,  $200,000 or more.
WATER, SOURCE OF.  Source of the water used by the occupants or intended
occupants  of  the housing  unit,  ascertained for  occupied and  vacant
housing units.  This item was asked on a sample basis.

     1. Public  system  or private  company.   A common  source  supplying
        running  water  to  six or  more  housing units.   The water  may
        be  supplied  by  a  city or  county water  department, a  water
        district, a private water  company, etc., or  it may be obtained
        from a well which supplies six or more housing units*

     2. Individual well.   Water obtained from  a  well on  the  property
        of  the unit being  enumerated  or  on a  neighboring  property
        providing water to  five or  fever  housing  units.  The  well
        water  may be hand  drawn,  wind  drawn,  or  engine  drawn;  piped
        or not piped; stored  in tanks;  or used directly from the well.

        Drilled.   A  well  generally  made with  a mechanical  drilling
        rig and less than 1  1/2  feet  in  diameter.  Drilled wells include
        artisian  (natural spring) wells.

        Dug.   A  well  generally hand  dug and  wider  than 1  1/2  feet
        in diameter.

     3. Some other source.  Water obtained from springs, creeks, rivers,
        ponds,  lakes,  cisterns,  or  other sources  not listed,  but  not
        from a public system, private company, or well.

In  the statistical  abstract  "other source*  of water supply  include
categories 2 and  3.
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