Census 2000 counted 115.9 million

housing units, 105.5 million of which

were occupied. Both measures surpassed the 102.3 million housing units

and 91.9 million occupied units recorded

in 1990.

This report, part of a series that presents

population and housing data collected

from Census 2000, examines the number of units in a structure, the year the

structure was built, the year the householder moved into the unit, and the

number of people per room. The 

report shows how these measures vary

geographically (by regions, states, counties, and large cities), by various household and housing characteristics, and

over time.

The Census Bureau began collecting data

on units in structure, year structure built,

and person per room in 1940, the first

Census of Housing. Data on the year the

householder moved into the unit were

first collected in 1960. Figure 1 is a

reproduction of how these items were

asked in Census 2000.

About 60 percent of all housing

units in 2000 were single-family,

detached units.1

Census 2000 divided the total housing

inventory into the ten categories presented in Table 1. A majority (60.3 percent)

were single-family houses not attached

to any other structure, down from 

63.3 percent in 1950.2 Another 5.6 percent were single-family houses attached

to one or more other structures (usually 

other homes). 

Units in buildings with two to four apartments comprised 9.1 percent of the housing inventory, while another 17.3 percent

were in buildings with five or more apartments. Mobile homes (also called “manufactured housing”) made up 7.6 percent of

the housing inventory. A tiny fraction

(0.2 percent) were classified as “other,”

which include boats, recreational vehicles,

and vans.

A high proportion of owner-occupied

units were single-family, detached homes

(80.6 percent). The second-largest category was mobile homes (8.4 percent).

Renters were much more likely than

owners to live in apartment buildings

with five or more units (44.7 percent).

Another 23.9 percent of renter households were in single-family, detached

houses, whereas 21.2 percent were in

buildings with two to four apartments.

The number of mobile homes grew

substantially in recent decades.

Classified as “trailers” in 1950, mobile

homes have been the fastest growing

type of housing — increasing in number

from 315,000 then to almost 8.8 million

in 2000, as shown in Figure 2. The total

U S C E N S U S B U R E A U

Helping You Make Informed Decisions

U.S.Department of Commerce

Economics and Statistics Administration

U.S. CENSUS BUREAU

Issued November 2003

C2KBR-32

Structural and Occupancy

Characteristics of Housing: 2000

Census 2000 Brief

By 

Robert Bennefield 

and 

Robert Bonnette

1 Single-family, detached homes are also referred

to as “1, detached.” Single-family, attached homes

are also labeled “1, attached” (see Table 1).

2 The estimates in this report are based on

responses from a sample of the population. As with

all surveys, estimates may vary from the actual values because of sampling variation or other factors.

All statements made in this report have undergone

statistical testing and are significant at the 90-

percent confidence level, unless otherwise noted.
2 U.S. Census Bureau

housing inventory during the same

period increased 152 percent.

The peak of mobile home growth

was in the 1970s and 1980s, when

their numbers increased over 

2.5 million during each decade. In

both percentage and absolute number, the growth of mobile homes

slowed in the 1990s, compared

with the previous two decades.

Largest households were in

single-family, detached houses.

In 2000, households in single-family,

detached houses, averaged 

2.81 people, compared with 2.59

for all occupied units. For all the

A mobile home

Which best describes this building? Include all

apartments, flats, etc., even if vacant.

A one-family house detached from any other house

A one-family house attached to one or more houses

A building with 2 apartments

A building with 3 or 4 apartments

A building with 5 to 9 apartments

A building with 10 to 19 apartments

A building with 20 to 49 apartments

A building with 50 or more apartments

Boat, RV, van, etc.

About when was this building first built?

1999 or 2000

1990 to 1994

1980 to 1989

1970 to 1979

1960 to 1969

1950 to 1959

1940 to 1949

1939 or earlier

1995 to 1998

Figure 1.

Reproduction of the Questions on Housing Occupancy and 

Structural Characteristics From Census 2000

Source: U.S. Census Bureau, Census 2000 questionnaire.

34

35

When did this person move into this house,

apartment, or mobile home?

1999 or 2000

1995 to 1998

1990 to 1994

1980 to 1989

1970 to 1979

1969 or earlier

36

How many rooms do you have in this house,

apartment, or mobile home? Do NOT count 

bathrooms, porches, balconies, foyers, halls, or 

half-rooms.

1 room

2 rooms

3 rooms

6 rooms

7 rooms

8 rooms

4 rooms

5 rooms

9 or more rooms

37

Table 1.

Units in Structure: 2000

(Data based on sample. For information on confidentiality protection, sampling error,

nonsampling error, and definitions, see www.census.gov/prod/cen2000/doc/sf3.pdf)

Type of structure

All housing units Owner occupied Renter occupied

Number Percent Number Percent Number Percent

Total ......... 115,904,641 100.0 69,816,513 100.0 35,663,588 100.0

1, detached ....... 69,865,957 60.3 56,255,657 80.6 8,531,853 23.9

1, attached ........ 6,447,453 5.6 3,819,810 5.5 2,087,994 5.9

2................. 4,995,350 4.3 1,164,675 1.7 3,301,854 9.3

3 or 4. . . . . . . . . . . . . 5,494,280 4.7 651,003 0.9 4,254,351 11.9

5 to 9. . . . . . . . . . . . . 5,414,988 4.7 488,081 0.7 4,332,461 12.1

10 to 19 . . . . . . . . . . 4,636,717 4.0 368,197 0.5 3,748,728 10.5

20 to 49 . . . . . . . . . . 3,873,383 3.3 407,561 0.6 3,049,458 8.6

50 or more ........ 6,134,675 5.3 725,672 1.0 4,798,031 13.5

Mobile home ...... 8,779,228 7.6 5,850,241 8.4 1,534,035 4.3

Other* . . . ......... 262,610 0.2 85,616 0.1 24,823 0.1

*Other includes, for example, boats, recreational vehicles, and vans.

Source: U.S. Census Bureau, Census 2000 Summary File 3.
other categories of housing, average

household size was below 2.59. In

fact, average household size

decreased as the number of units in

a structure increased, reaching a low

of 1.82 for apartments in buildings

with 50 or more units.3

Homes that were owned averaged

2.71 people and renting households averaged 2.36 people.

However, renters in single-family,

detached houses averaged 2.92

people, higher than the 2.79 for

owners. The same pattern held for

apartments in structures with five

or more units. For example,

renters in units in buildings with

50 or more apartments had an

average household size of 1.84,

compared with 1.69 for owners.

Most households, but not

those with householders

under aged 25, lived in 

single-family houses.4

About two-thirds of all households

lived in single-family units. The

percent was lowest (28.1 percent)

for householders under age 25, as

shown in Figure 3. It rose with

age of householder, peaking for

householders in the next two age

groups (45 to 54 and 55 to 64) at

about 75 percent. After that,

households in single-family units

fell over the next two age groups,

to 67 percent at 75 and over.

Among owners, a majority of every

age group, including the youngest,

lived in single-family homes.

Householders under 25 were least

likely to live in one-family homes

(64.4 percent), whereas those 45

to 54 were most likely (89 percent). The proportion then

declined at older ages.

Among renters, in no age group

did a majority of householders live

in single-family houses. The peak

percentage occurred among householders 35 to 44 (36.2 percent).

Incomes were highest for

households in single-family

houses; lowest for those 

in structures with five or

more apartments.

Median household income in 1999

was $41,851 for all households

and $50,739 for those in singlefamily homes. For those in apartments, the lowest median incomes

were $27,543 for households in

buildings with five or more units

and $29,323 for those in apartments with two to four units.

Households in mobile homes had a

median income of $28,041.

Housing units built before

1940 outnumbered units 

built between 1995 and 

March 2000.

Census 2000 counted 17.4 million

old units, defined as those built

before 1940, or 15 percent of the

total housing units. In contrast,

9.7 percent of the total inventory,

or 11.2 million were new units,

those built between 1995 and

March 2000.

Owners were more likely than

renters to live in new homes.

Of the 69.8 million owner-occupied

units in 2000, 11 percent were

built between 1995 and March

2000, higher than the percentage

of new units occupied by renters

(6.4 percent). On the other hand,

renters were more likely than owners to live in old homes (16.3 compared with 14.2 percent).

Only householders aged 25 to

34 were more likely to live in

new than old homes.

Among householders 25 to 34,

14.5 percent lived in new and 

13.6 percent lived in old homes,

whereas householders at other

ages were more likely to live in old

homes. For example, among

householders under 25, 12.6 percent lived in old homes and 

11.5 percent lived in new homes.

Figure 4 shows that the proportion

living in old homes rose with the

age of the householder.

U.S. Census Bureau 3

Figure 2.

Number of Mobile Homes: 1950 to 2000

Source: U.S. Census Bureau, Census of Population and Housing, decennial volumes.

(Numbers in thousands. Data based on sample. For more information 

on confidentiality protection, sampling error, nonsampling error, and 

definitions, see www.census.gov/prod/cen2000/doc/sf3.pdf)

2000

1990

1980

1970

1960

1950 315

767

2,073

4,664

7,400

8,779

3 Units classified as “Boat, RV, van, etc.” are

not generally covered in the text because of

their small number: only 110,000 nationally. 4 Single-family houses are defined as one

(unit), detached or attached; mobile homes

are excluded.
Incomes were higher for

households in new units.

Median household income in 1999

was $52,990 for those living in

new homes, higher than the

median of $41,851 for all occupied

units. Households in old units

reported a lower median income 

of $37,033.

New and old occupied 

units were primarily singlefamily homes.

About two-thirds of new occupied

units (66.1 percent) were singlefamily houses, either detached or

attached, while 69.3 percent of old

ones were single-family houses.

About 15.1 percent of new units

were mobile homes; 17.1 percent

of old units were apartments in

buildings with two to four units.

Other categories of new and old

units constituted smaller percentages, as shown in Table 2.

Among renters living in new housing, the most common structural

type was apartment buildings of 5

to 19 units, which were home to

29.9 percent of renter households

living in new housing. Renters in

old housing were slightly more

likely to live in single-family homes

(34.8 percent) than homes with

two to four units (32.7 percent).

Recent movers (moved in 

the 15 months before Census

2000) outnumbered “stayers”

(last move was before 1970).

Of the country’s 105.5 million

households, 19.9 percent of householders reported having moved into

their residence in the 15 months

prior to Census 2000 (1999 to

March 2000). This proportion was

about double that of householders

who were “stayers,” that is, who

had not moved in over 30 years, or

before 1970 (9.7 percent).

Among homeowners, stayers 

outnumbered recent movers 

(13.5 percent compared with 

10.3 percent). Renters were far

more mobile: 38.8 percent were

recent movers, while 2.1 percent

had lived in the same residence for

over 30 years.

Recent movers outnumbered

stayers until householders

reached ages 55 to 64.

Householders below the age of 55

were far more likely to be recent

movers than stayers; the proportions then reversed in the 55-to-64

age group (see Figure 5). Over twothirds of those under the age of 25

were recent movers. This percentage declined by age, dropping to

5.8 percent for those aged 75 to

84; however, the rate then went up

slightly to 6.5 percent for householders 85 and over. Conversely,

the likelihood of living in the same

home over 30 years increased by

age of householder, reaching 

38.5 percent for those 85 and over.5

4 U.S. Census Bureau

Figure 3.

Percent of Households Living in Single-Family Houses 

by Tenure and Age of Householder: 2000

Source: U.S. Census Bureau, Census 2000 Summary File 3.

(Data based on sample. For more information on confidentiality protection, 

sampling error, nonsampling error, and definitions, 

see www.census.gov/prod/cen2000/doc/sf3.pdf) Renter

Owner

All occupied

75 and over

65 to 74

55 to 64

45 to 54

35 to 44

25 to 34

Under 25

67.0

20.6

64.4

28.1

28.9

81.9

52.9

36.2

87.8

70.4

34.7

89.0

75.4

31.2

87.1

75.6

26.5

85.2

74.0

21.1

83.1

5 There was no significant difference

between the percentages for stayers 85 and

over (38.5 percent) and recent movers 25 to

34 years of age (38.3 percent).
U.S. Census Bureau 5

White and Black householders

tended to be less mobile 

than other races.

Census 2000 allowed respondents

to choose more than one race. With

the exception of the Two or more

races group, all race groups discussed in this report refer to people

who indicated only one racial identity among the six major categories:

White, Black or African American,

American Indian and Alaska Native,

Asian, Native Hawaiian or Other

Pacific Islander, and Some Other

Race.6 The use of the single-race

population in this report does not

imply that it is the preferred

method of presenting or analyzing

data. The Census Bureau uses a

variety of approaches.7

About 18.5 percent of White and

23 percent of Black householders

were recent movers. For each of

the other race groups, a higher

proportion were recent movers as

shown in Figure 6. Householders

reporting themselves as Some

Other Race were the most likely to

be recent movers (30.6 percent).

Hispanic or Latino householders

(who may be of any race) were far

more likely to be recent movers

than non-Hispanic Whites: 28.2 percent compared with 18 percent.

Of the seven racial categories

shown in Figure 6, only for White

householders did the proportion of

stayers exceed 10 percent, with

Black householders second at 

8.5 percent. Only 2.7 percent of

those reporting Some Other Race

were stayers.

Differences among groups may

reflect differences in age composition. Figure 5 showed that young

householders were most likely to

have moved recently. Groups with

high proportions of young householders might have high rates 

of moving.

Renter-occupied housing 

was more likely to be 

crowded (more than one

person per room).

Occupied units are generally considered crowded if they have more

than one person per room and

severely crowded if more than 

1.5 persons per room. Nationally,

5.7 percent of all occupied units

were crowded and 2.7 percent

severely crowded. The figures

were much higher for renters: 

11 percent were crowded and 

5.8 percent severely crowded; for

owners, the proportions were 3.1

and 1.2 percent, respectively.

Single-family, detached 

homes were the least likely 

to be crowded.

Only 3.4 percent of households in

single-family, detached houses

were crowded, with 1.3 percent

considered severely crowded.

Overcrowding was more common

in each of the other types of housing shown in Figure 7. The highest rates (11 percent crowded and

Figure 4.

Percent of Households Living in New and Old Homes 

by Age of Householder: 2000

Source: U.S. Census Bureau, Census 2000 Summary File 3.

(Data based on sample. For more information on confidentiality protection, 

sampling error, nonsampling error, and definitions, 

see www.census.gov/prod/cen2000/doc/sf3.pdf)

New homes (built 1995 - March 2000)

Old homes (built before 1940)

75 and over

65 to 74

55 to 64

45 to 54

35 to 44

25 to 34

Under 25

19.8

11.5

12.6

14.5

13.6

11.7

13.9

8.3

14.5

7.1

14.9

5.8

16.3

4.2

7 This report draws heavily on Summary

File 3, a Census 2000 product that can be

accessed through American FactFinder, available from the Census Bureau’s Web site,

www.census.gov. Information on people who

reported more than one race, such as “White

and American Indian and Alaska Native” or

“Asian and Black or African American,” is in

Summary File 4, also available through

American FactFinder. About 2.6 percent of

people reported more than one race.

6 For further information on each of the

six major race groups, and the Two or more

races population, see reports from the

Census 2000 Brief series (C2KBR/01), available on the Census 2000 Web site at

www.census.gov/population/wwwcen2000

/briefs.html.
6.4 percent severely crowded)

occurred in units in buildings with

five or more apartments.

Crowded and severely

crowded households had

much lower incomes than 

did all households.

Median household income in 1999

was $41,851 for all occupied units.

Crowded households reported a

median of $35,328 and severely

crowded households still lower 

at $32,983.

White and Black householders

were the least likely to live 

in crowded units.

In this section, race is that of the

householder. Nationally, 3.1 percent of White households and 

8.5 percent of Black households

had more than one person per

room. As can be seen in Table 3,

all the other race groups had rates

over 10 percent, with Some Other

Race the highest at 35.2 percent.

The same general pattern held for

severely crowded households:

White households and Black households had the lowest rates 

(1.3 percent and 3.3 percent,

respectively). Among the racial

groups, Some Other Race households had the highest at 20.8 percent severely crowded.

For Hispanic or Latino households,

29.3 percent were crowded and 

17 percent severely crowded. By

comparison, only 1.9 percent of

non-Hispanic White households

were crowded and a mere 0.6 percent were severely crowded.

GEOGRAPHIC DISTRIBUTION

OF STRUCTURAL AND

OCCUPANCY

CHARACTERISTICS

The proportion of singlefamily homes was highest in

the Midwest and lowest 

in the Northeast.8

Single-family houses, whether

detached or attached, topped 

70 percent in only one region — the

Midwest (see Table 4). Units in

buildings with two to four units in

structure were most prevalent in

the Northeast, making up 16.3 percent of the total housing in that

region. The highest concentrations

of units in buildings with five or

more apartments were in the

Northeast and West, where they

comprised 21.3 percent and 

20 percent, respectively, of the

housing inventory.

6 U.S. Census Bureau

Table 2.

New and Old Units by Tenure and Units in Structure: 2000

(Data based on sample. For information on confidentiality protection, sampling error,

nonsampling error, and definitions, see www.census.gov/prod/cen2000/doc/sf3.pdf)

Type of structure

New units

(built 1995 to March 2000)

Old units

(built 1939 or earlier)

Number Percent Number Percent

All occupied housing units. . 9,945,989 100.0 15,735,979 100.0

1, detached or attached .......... 6,571,383 66.1 10,899,321 69.3

2 to 4 . . . . . . . . . . . . . . . . . . . . . . . . . . 418,344 4.2 2,690,493 17.1

5 to 19 . . . . . . . . . . . . . . . . . . . . . . . . . 761,656 7.7 1,019,574 6.5

20 to 49 . . . . . . . . . . . . . . . . . . . . . . . . 266,309 2.7 497,164 3.2

50 or more. ..................... 405,968 4.1 530,300 3.4

Mobile home .................... 1,499,754 15.1 94,129 0.6

Other*. . . ....................... 22,575 0.2 4,998 0.0

Owner-occupied housing units . . 7,654,775 100.0 9,935,649 100.0

1, detached or attached .......... 6,094,464 79.6 8,879,565 89.4

2 to 4 . . . . . . . . . . . . . . . . . . . . . . . . . . 68,355 0.9 796,472 8.0

5 to 19 . . . . . . . . . . . . . . . . . . . . . . . . . 77,020 1.0 82,807 0.8

20 to 49 . . . . . . . . . . . . . . . . . . . . . . . . 20,726 0.3 49,266 0.5

50 or more. ..................... 29,700 0.4 70,508 0.7

Mobile home .................... 1,344,519 17.6 54,754 0.6

Other*. . . ....................... 19,991 0.3 2,277 0.0

Renter-occupied housing units . . 2,291,214 100.0 5,800,330 100.0

1, detached or attached .......... 476,919 20.8 2,019,756 34.8

2 to 4 . . . . . . . . . . . . . . . . . . . . . . . . . . 349,989 15.3 1,894,021 32.7

5 to 19 . . . . . . . . . . . . . . . . . . . . . . . . . 684,636 29.9 936,767 16.2

20 to 49 . . . . . . . . . . . . . . . . . . . . . . . . 245,583 10.7 447,898 7.7

50 or more. ..................... 376,268 16.4 459,792 7.9

Mobile home .................... 155,235 6.8 39,375 0.7

Other*. . . ....................... 2,584 0.1 2,721 0.0

*Other includes, for example, boats, recreational vehicles, and vans.

Source: U.S. Census Bureau, Census 2000 Summary File 3.

8 The Northeast region includes the states

of Connecticut, Maine, Massachusetts, New

Hampshire, New Jersey, New York,

Pennsylvania, Rhode Island, and Vermont.

The Midwest region includes the states of

Illinois, Indiana, Iowa, Kansas, Michigan,

Minnesota, Missouri, Nebraska, North Dakota,

Ohio, South Dakota, and Wisconsin. The

South region includes the states of Alabama,

Arkansas, Delaware, Florida, Georgia,

Kentucky, Louisiana, Maryland, Mississippi,

North Carolina, Oklahoma, South Carolina,

Tennessee, Texas, Virginia, West Virginia, and

the District of Columbia, a state equivalent.

The West region includes the states of Alaska,

Arizona, California, Colorado, Hawaii, Idaho,

Montana, Nevada, New Mexico, Oregon, Utah,

Washington, and Wyoming.
Over half of the nation’s

mobile homes were in 

the South.

The 4.9 million mobile homes in

the South represented 56.1 percent

of the U.S. total. In 1990, the

South’s 3.8 million mobile homes

were 51.8 percent of the nation’s

mobile homes. The West was second in both 2000 and 1990, with a

total of 1.7 million in 2000, up a

little from the 1.6 million reported

in the 1990 census. Mobile homes

in 2000 made up 11.6 percent of

the South’s total housing inventory

and 7.1 percent in the West.

New homes were most

common in the South and

West; old homes in the

Northeast and the Midwest.

In the South, 12.7 percent of the

total inventory was new (built

1995 to March 2000). The West

was second at 10.5 percent. New

housing was much scarcer in the

Midwest and Northeast, constituting 8.4 percent and 4.7 percent,

respectively, of the housing stock.

U.S. Census Bureau 7

Figure 5.

Percent of Householders Who Were Recent Movers 

or Stayers by Age of Householder: 2000

Source: U.S. Census Bureau, Census 2000 Summary File 3.

(Data based on sample. For more information on confidentiality protection, 

sampling error, nonsampling error, and definitions, 

see www.census.gov/prod/cen2000/doc/sf3.pdf)

85 and over

75 to 84

65 to 74

55 to 64

45 to 54

35 to 44

25 to 34

Under 25

38.5

68.7

0

38.3

0.5

20.2

1.5

13.1

2.6

9.8

12.3

6.9

28.5

5.8

36.9

6.5

Recent movers (moved 1999 to March 2000)

Stayers (last moved before 1970)

Table 3.

Crowded and Severely Crowded Units by Race and Hispanic Origin of Householder: 2000

(Data based on sample. For information on confidentiality protection, sampling error, nonsampling error, and definitions, see

www.census.gov/prod/cen2000/doc/sf3.pdf)

Race and Hispanic origin of householder

Total

Crowded Severely crowded

Number Percent Number Percent

All occupied housing units................. 105,480,101 6,057,890 5.7 2,873,122 2.7

White alone .................................... 83,715,168 2,610,428 3.1 1,107,517 1.3

White alone, not Hispanic or Latino ............. 79,086,566 1,494,709 1.9 475,430 0.6

Black or African American alone .................. 11,977,309 1,022,069 8.5 397,300 3.3

American Indian or Alaska Native alone ........... 765,474 113,467 14.8 56,302 7.4

Asian alone . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3,117,356 638,335 20.5 345,132 11.1

Native Hawaiian or other Pacific Islander alone .... 98,739 25,361 25.7 13,064 13.2

Some other race alone .......................... 3,835,590 1,351,974 35.2 796,256 20.8

Two or more races.............................. 1,970,465 296,256 15.0 157,551 8.0

Hispanic or Latino (of any race) .................. 9,179,764 2,692,348 29.3 1,563,600 17.0

Source: U.S. Census Bureau, Census 2000 Summary File 3.
The Northeast (28.9 percent) and

the Midwest (21.2 percent) showed

the highest proportion of housing

inventories built before 1940. Old

units were rarer in the South, making up only 7.2 percent of all housing in that region. The West had

the smallest difference between

new and old units among the

regions with 10.5 percent new

units and 9.1 percent old.

Recent movers were 

most common in the West 

and South.

Census 2000 reported 23 percent

of householders in the West and

21.5 percent in the South had

moved in the previous 15 months

(see Table 5). Householders who

had not moved in over 30 years

were more prevalent in the

Northeast and Midwest. The

Northeast was the most balanced

region, with 15.5 percent recent

movers and 13.8 percent stayers.

Iowa led all states in the

proportion of its housing

units in single-family houses.

The four states with the highest

percentage of total housing units

that were single-family houses,

were all in the Midwest (see 

Table 4): Iowa (76.3 percent),

Kansas (75.9 percent), Nebraska

(74.8 percent), and Michigan 

(74.5 percent).9 Other states with

high percentages of single-family

houses were Idaho, Indiana,

Minnesota, Oklahoma,

Pennsylvania, and Utah. New York

was the only state where less than

one-half of its housing units were

single-family houses (46.6 percent),

although the District of Columbia

was lower at 39.7 percent.

Homes in structures with 

two to four units were 

most common in the

northeastern states. 

The five states with the highest percentage of the housing inventory in

two-to-four-unit structures were all

in the Northeast: Rhode Island

(25.2 percent), Massachusetts 

(23 percent), New York (18.2 percent), Connecticut (17.8 percent),

and New Jersey (16.8 percent).

This primarily older type of housing

fell from 13 percent of all housing

nationally in 1960 to 9.1 percent by

2000. Since the Northeast had the

highest proportion of old homes in

2000, the two-to-four-unit structure,

often two or three family flats on

different floors, has endured in 

that region.

Hawaii and New York topped

all states in the proportion of

housing in buildings with five

or more apartments.

Hawaii and New York were not significantly different, with about

32.5 percent of their homes in

structures with five or more apartments. Nevada, California, and

8 U.S. Census Bureau

Figure 6.

Percent of Householders Who Were Recent Movers 

or Stayers by Race and Hispanic Origin 

of Householder: 2000

Source: U.S. Census Bureau, Census 2000 Summary File 3.

(Data based on sample. For more information on confidentiality protection, 

sampling error, nonsampling error, and definitions, 

see www.census.gov/prod/cen2000/doc/sf3.pdf)

Recent movers (moved 1999 to March 2000)

Stayers (last moved before 1970)

White alone, not

Hispanic or Latino

Hispanic or Latino

(any race)

Two or more races

Some other race alone

Native Hawaiian or

other Pacific Islander alone

Asian alone

American Indian

or Alaska Native alone

Black or African

American alone

White alone

4.1

18.5

10.5

23.0

8.5

25.5

5.3

27.4

3.2

28.8

4.9

30.6

2.7

28.6

4.6

18.0

10.8

28.2

9 There was no statistical difference

between Nebraska and Michigan.
Florida (about 23 percent each)

rounded out the five states with

very high percentages of this housing type. The District of Columbia

was even higher at 49.2 percent.

At the other end of the scale, West

Virginia was the state with the lowest percentage (6.5 percent) of its

housing in buildings with five or

more apartments.

California (2.8 million) and New

York (2.5 million) led all the states

in numbers of housing units in

structures with five or more units.

Florida, Texas, and Illinois were the

other three states with more than

1 million such units. These five

states accounted for almost half of

all housing in structures with five

or more units nationally.

For mobile homes, South

Carolina led in percentage,

while Florida was the leader

in total number.

South Carolina was the only state

where mobile homes composed

over 20 percent of the total housing inventory; New Mexico came in

second at 18.6 percent. In another

five states mobile homes were at

least 15 percent of all housing

units (or about twice the national

percentage); four of these states

(Alabama, Mississippi, North

Carolina, and West Virginia) were in

the South, and the fifth (Wyoming)

was in the West. 

Florida led all states in the number

of mobile homes with 849,000,

followed by Texas with 732,000.

North Carolina was third at

577,000. In all, 11 states had

more than one-quarter million

mobile homes. The remaining

eight, in order of their total number, were California, Georgia, South

Carolina, Alabama, Arizona,

Michigan, Tennessee, and

Pennsylvania.

Nevada led in percentage 

of new homes; Texas topped

the list in the number of 

new units.

Over one-quarter of Nevada’s

housing (26.2 percent) was built

between 1995 and March 2000, the

only state topping the 20-percent

mark. Neighboring Arizona 

(18.8 percent) and Utah (17.4 percent) were second and third.

Georgia and North Carolina were

the only other two states with new

housing inventories above 

16 percent.

Texas was the only state with more

than 1 million new units, more than

the entire Northeast region. Four

other states had over one-half million new units: California, Florida,

Georgia, and North Carolina.

Massachusetts led all states 

in the percentage of old units,

New York in the number of

such units.

Units built before 1940 were 

34.5 percent of the housing inventory in Massachusetts (not significantly different from the District of

Columbia). Eight states had more

than one-quarter of their housing

inventory built before 1940; these

included Iowa, Maine, Massachusetts, Nebraska, New York,

Pennsylvania, Rhode Island, 

and Vermont.

New York had the largest number

of old units (2.4 million), more

than the entire West region. Four

other states had more than 1 million old units: California, Illinois,

Ohio, and Pennsylvania.

U.S. Census Bureau 9

Figure 7.

Percent of Housing Units That Were Crowded or 

Severely Crowded by Units in Structure: 2000

Source: U.S. Census Bureau, Census 2000 Summary File 3.

(Data based on sample. For more information on confidentiality 

protection, sampling error, nonsampling error, and definitions, 

see www.census.gov/prod/cen2000/doc/sf3.pdf)

Mobile home

5 or more

2 to 4

1, attached

1, detached

All occupied

2.6

5.7

2.7

3.4

1.3

7.7

3.8

9.8

4.7

11.0

6.4

6.8 

Crowded (more than 1 person per room)

Severely crowded (more than 1.5 persons per room)
10 U.S. Census Bureau

Table 4.

Structural Characteristics for the United States, Regions, and States, and for

Puerto Rico: 2000

(Data based on sample. For information on confidentiality protection, sampling error, nonsampling error, and definitions, see

www.census.gov/prod/cen2000/doc/sf3.pdf)

Area All

housing

units

Units in structure

(percent)

Year structure built

(percent)

1, detached

or attached 2 to 4 5 or more Mobile home

New homes

(built 1995 to

March 2000)

Old homes

(built before

1940)

United States ........... 115,904,641 65.8 9.1 17.3 7.6 9.7 15.0

Region

Northeast................... 22,180,440 59.4 16.3 21.3 3.0 4.7 28.9

Midwest .................... 26,963,635 70.9 9.0 14.5 5.4 8.4 21.2

South...................... 42,382,546 66.5 6.2 15.4 11.6 12.7 7.2

West . . . . . . . . . . . . . . . . . . . . . . 24,378,020 64.9 7.5 20.0 7.1 10.5 9.1

State

Alabama ................... 1,963,711 68.2 5.5 9.8 16.3 13.0 7.1

Alaska ..................... 260,978 65.5 12.8 14.2 6.8 11.1 2.1

Arizona .................... 2,189,189 62.8 4.9 17.2 13.8 18.8 2.2

Arkansas ................... 1,173,043 70.8 6.2 7.7 14.9 13.1 7.0

California ................... 12,214,549 64.0 8.4 23.0 4.4 6.0 9.4

Colorado ................... 1,808,037 68.4 5.8 19.9 5.7 15.0 10.3

Connecticut ................. 1,385,975 64.1 17.8 17.3 0.8 4.5 22.3

Delaware ................... 343,072 70.0 4.6 14.1 11.2 11.2 10.7

District of Columbia ........... 274,845 39.7 11.0 49.2 0.1 1.4 34.6

Florida ..................... 7,302,947 58.1 7.0 22.9 11.6 12.2 2.9

Georgia .................... 3,281,737 67.1 6.8 14.0 12.0 16.6 5.9

Hawaii ..................... 460,542 60.3 6.9 32.5 0.2 7.7 4.7

Idaho ...................... 527,824 73.0 6.8 7.5 12.2 15.6 11.5

Illinois ..................... 4,885,615 62.8 13.4 20.6 3.2 6.9 22.6

Indiana..................... 2,532,319 74.1 7.3 11.9 6.6 10.2 20.2

Iowa....................... 1,232,511 76.3 7.1 11.3 5.3 7.3 31.6

Kansas .................... 1,131,200 75.9 6.6 11.0 6.4 8.7 20.1

Kentucky ................... 1,750,927 68.1 7.3 10.4 14.1 12.5 12.4

Louisiana ................... 1,847,181 67.9 8.6 10.2 13.0 8.9 8.5

Maine...................... 651,901 69.6 11.5 8.8 9.8 7.5 29.1

Maryland ................... 2,145,283 72.2 5.1 20.8 1.9 8.4 12.5

Massachusetts............... 2,621,989 56.4 23.0 19.6 0.9 4.3 34.5

Michigan ................... 4,234,279 74.5 6.2 12.5 6.5 8.6 16.9

Minnesota .................. 2,065,946 73.0 5.3 16.9 4.5 8.9 20.7

Mississippi .................. 1,161,953 69.9 5.8 7.5 16.6 13.3 6.2

Missouri .................... 2,442,017 71.5 9.0 11.0 8.2 9.8 16.2

Montana ................... 412,633 69.7 7.9 7.8 14.3 10.9 17.5

Nebraska ................... 722,668 74.8 5.6 14.4 5.1 8.2 25.3

Nevada .................... 827,457 57.7 8.8 23.3 9.7 26.2 1.7

New Hampshire.............. 547,024 66.8 12.5 14.0 6.5 7.1 23.7

New Jersey ................. 3,310,275 62.8 16.8 19.4 1.0 5.7 20.1

New Mexico................. 780,579 65.5 5.5 9.9 18.6 14.0 5.9

New York . . . . . . . . . . . . . . . . . . . 7,679,307 46.6 18.2 32.4 2.7 3.5 31.2

North Carolina ............... 3,523,944 67.4 5.8 10.3 16.4 16.4 7.3

North Dakota ................ 289,677 66.1 6.8 18.0 9.0 7.8 20.3

Ohio....................... 4,783,051 71.2 9.9 14.2 4.6 7.5 22.5

Oklahoma .................. 1,514,400 73.8 4.7 10.4 10.7 8.4 10.3

Oregon .................... 1,452,709 66.0 7.2 15.8 10.3 13.1 13.4

Pennsylvania ................ 5,249,750 73.8 9.8 11.3 4.9 5.3 30.3

Rhode Island ................ 439,837 57.7 25.2 16.0 1.0 4.1 29.4

South Carolina............... 1,753,670 63.8 5.8 10.0 20.3 15.4 6.1

South Dakota................ 323,208 69.6 6.4 12.6 11.4 9.5 24.1

Tennessee .................. 2,439,443 70.1 6.8 11.9 11.0 13.9 7.9

Texas...................... 8,157,575 66.5 5.4 18.7 9.0 13.2 5.4

Utah....................... 768,594 72.6 8.6 13.4 5.1 17.4 10.0

Vermont .................... 294,382 69.1 13.6 9.4 7.7 6.7 30.0

Virginia .................... 2,904,192 72.0 5.3 16.2 6.4 10.6 9.1

Washington ................. 2,451,075 65.4 6.6 19.0 8.5 11.7 12.5

West Virginia ................ 844,623 70.7 5.5 6.5 16.9 8.8 19.3

Wisconsin .................. 2,321,144 69.3 12.1 14.0 4.4 9.5 23.4

Wyoming ................... 223,854 68.5 7.1 8.1 15.9 9.3 13.9

Puerto Rico ................ 1,418,476 83.7 5.1 10.8 0.4 10.8 2.7

Source: U.S. Census Bureau, Census 2000 Summary File 3.
U.S. Census Bureau 11

Table 5.

Occupancy Characteristics for the United States, Regions, and States, and for

Puerto Rico: 1990 and 2000

(Data based on sample. For information on confidentiality protection, sampling error, nonsampling error, and definitions, see

www.census.gov/prod/cen2000/doc/sf3.pdf)

Area

1990 2000

All

occupied

housing

units

(Percent) All

occupied

housing

units

(Percent)

Recent

movers Stayers Crowded

Severely

crowded

Recent

movers Stayers Crowded

Severely

crowded

United States ........ 91,947,410 20.9 9.1 4.9 2.1 105,480,101 19.9 9.7 5.7 2.7

Region

Northeast................ 18,872,713 15.5 12.7 3.9 1.5 20,285,622 15.5 13.8 4.6 2.0

Midwest ................. 22,316,975 18.9 10.4 2.5 0.7 24,734,532 18.5 11.0 2.9 1.0

South................... 31,822,254 22.4 8.2 4.8 1.8 38,015,214 21.5 8.5 5.2 2.2

West . . . . . . . . . . . . . . . . . . . 18,935,468 26.1 5.6 9.1 4.9 22,444,733 23.0 6.5 10.9 6.1

State

Alabama ................ 1,506,790 19.1 10.9 3.5 0.9 1,737,080 18.9 11.3 2.9 0.9

Alaska .................. 188,915 33.0 1.6 8.6 3.9 221,600 25.8 2.5 8.6 4.0

Arizona ................. 1,368,843 28.7 3.3 7.4 3.4 1,901,327 26.8 3.7 8.6 4.2

Arkansas ................ 891,179 21.0 8.8 3.7 0.9 1,042,696 21.6 8.6 3.7 1.1

California ................ 10,381,206 25.6 5.4 12.3 7.1 11,502,870 21.4 6.9 15.2 9.1

Colorado ................ 1,282,489 27.4 5.1 3.0 1.1 1,658,238 25.8 5.5 4.6 2.1

Connecticut .............. 1,230,479 16.7 11.9 2.3 0.6 1,301,670 16.9 13.4 2.8 1.0

Delaware ................ 247,497 19.0 9.7 2.3 0.6 298,736 17.7 11.0 2.8 1.0

District of Columbia ........ 249,634 20.6 9.8 8.2 4.4 248,338 22.9 11.4 8.9 5.3

Florida .................. 5,134,869 24.5 3.9 5.8 2.6 6,337,929 22.4 4.3 6.5 3.1

Georgia ................. 2,366,615 23.8 7.4 4.0 1.2 3,006,369 22.9 7.6 4.8 1.9

Hawaii .................. 356,267 23.2 8.4 15.9 7.8 403,240 20.2 11.9 15.4 7.7

Idaho ................... 360,723 24.2 7.6 4.2 1.2 469,645 22.4 6.9 4.9 1.7

Illinois .................. 4,202,240 18.8 9.8 4.0 1.4 4,591,779 18.2 10.5 4.8 2.1

Indiana.................. 2,065,355 19.1 10.6 2.2 0.4 2,336,306 19.6 11.0 2.3 0.7

Iowa.................... 1,064,325 18.1 12.1 1.5 0.4 1,149,276 17.9 12.3 2.0 0.7

Kansas ................. 944,726 21.9 10.0 2.5 0.7 1,037,891 21.3 9.8 3.0 1.1

Kentucky ................ 1,379,782 19.3 9.8 2.6 0.5 1,590,647 19.8 10.2 2.1 0.5

Louisiana ................ 1,499,269 20.1 11.0 6.0 1.8 1,656,053 18.7 11.7 5.2 1.8

Maine................... 465,312 18.1 11.0 1.7 0.4 518,200 17.2 11.2 1.3 0.3

Maryland ................ 1,748,991 19.3 9.2 3.0 1.1 1,980,859 18.0 10.0 3.6 1.5

Massachusetts............ 2,247,110 17.2 12.3 2.5 0.8 2,443,580 16.4 13.4 2.8 1.1

Michigan ................ 3,419,331 18.1 10.3 2.6 0.7 3,785,661 17.5 11.2 3.0 1.0

Minnesota ............... 1,647,853 19.4 10.4 2.1 0.7 1,895,127 17.6 10.0 2.9 1.3

Mississippi . . . . . . . . . . . . . . . 911,374 18.6 10.9 5.8 1.8 1,046,434 18.7 10.9 4.9 1.5

Missouri ................. 1,961,206 20.1 9.1 2.5 0.6 2,194,594 20.0 9.5 2.4 0.7

Montana ................ 306,163 22.7 9.2 2.9 0.8 358,667 21.3 8.7 3.1 1.0

Nebraska ................ 602,363 19.9 10.2 1.7 0.5 666,184 20.1 10.6 2.7 1.1

Nevada ................. 466,297 35.3 2.1 6.4 2.9 751,165 30.4 2.2 8.6 4.3

New Hampshire. . . . . . . . . . . 411,186 19.5 8.0 1.6 0.3 474,606 18.0 8.5 1.6 0.4

New Jersey .............. 2,794,711 15.2 11.2 3.9 1.3 3,064,645 15.6 12.3 5.0 2.1

New Mexico.............. 542,709 23.8 7.6 7.9 3.3 677,971 22.1 8.1 7.5 3.2

New York . . . . . . . . . . . . . . . . 6,639,322 14.9 11.5 6.5 2.8 7,056,860 15.0 13.1 7.8 3.8

North Carolina ............ 2,517,026 20.2 10.7 2.9 0.7 3,132,013 20.8 10.4 3.4 1.2

North Dakota ............. 240,878 20.2 10.9 2.0 0.5 257,152 19.5 10.8 2.0 0.6

Ohio.................... 4,087,546 18.0 11.0 1.8 0.3 4,445,773 17.9 12.5 1.7 0.4

Oklahoma ............... 1,206,135 23.4 8.3 3.3 0.9 1,342,293 22.6 8.5 3.7 1.2

Oregon ................. 1,103,313 25.3 6.2 3.6 1.4 1,333,723 24.1 5.9 4.8 2.1

Pennsylvania ............. 4,495,966 14.2 16.5 1.8 0.5 4,777,003 14.6 17.0 1.9 0.6

Rhode Island ............. 377,977 18.1 12.3 2.3 0.6 408,424 17.8 13.3 2.9 0.9

South Carolina............ 1,258,044 19.8 10.3 4.1 1.1 1,533,854 19.7 10.6 3.2 1.0

South Dakota............. 259,034 20.2 10.7 3.0 1.0 290,245 19.6 10.1 3.0 1.1

Tennessee ............... 1,853,725 21.2 9.5 2.7 0.7 2,232,905 20.7 9.8 2.7 0.8

Texas................... 6,070,937 26.7 6.9 8.1 3.6 7,393,354 24.9 7.2 9.4 4.5

Utah.................... 537,273 24.6 9.4 5.5 1.4 701,281 24.0 8.6 6.0 2.3

Vermont ................. 210,650 19.9 9.8 1.7 0.4 240,634 17.1 10.3 1.4 0.4

Virginia ................. 2,291,830 21.9 8.5 2.8 0.9 2,699,173 20.3 9.3 3.2 1.3

Washington .............. 1,872,431 26.3 6.4 3.9 1.6 2,271,398 23.4 6.5 5.1 2.4

West Virginia ............. 688,557 15.3 14.8 1.9 0.3 736,481 15.3 14.8 1.3 0.3

Wisconsin ............... 1,822,118 18.6 11.1 2.1 0.5 2,084,544 18.4 11.0 2.4 0.8

Wyoming ................ 168,839 25.0 7.4 2.8 0.7 193,608 22.7 7.6 2.7 0.9

Puerto Rico ............. 1,054,924 15.0 10.8 12.1 3.5 1,261,325 12.5 14.2 19.3 8.3

Source: U.S. Census Bureau, 1990 census and Census 2000 Summary File 3.
Householders in Nevada 

were the most likely to be

recent movers.

In Nevada, 30 percent of all householders had moved in during the

15 months prior to Census 2000.

The percentage of recent movers

exceeded 25 percent but less than

30 percent in three other states:

Alaska, Arizona, and Colorado 

(see Table 5).

Nationally, householders were a bit

less likely to be recent movers in

2000 than in 1990 (20 percent and

21 percent, respectively). Among

the regions, this decline was very

pronounced in the West, where

recent movers were 23 percent of

householders in 2000 and 26 percent in 1990. Alaska showed the

largest drop, from 33 percent in

1990 to 26 percent in 2000, but

was still among the four states

with the highest proportion of

recent-mover householders.

Stayers were more common

than recent movers only 

in Pennsylvania.

In Pennsylvania, 17 percent of 

all householders had lived in the

same home for more than 

30 years, while 14.6 percent were

recent movers; in every other

state, recent movers exceeded

stayers. West Virginia had the

smallest difference between stayers and recent movers with 

14.8 percent stayers and 15.3 percent recent movers. Stayers were

under 5 percent in four rapidly

growing states: Alaska, Arizona,

Florida, and Nevada.

Households in California 

and Hawaii were most likely 

to be crowded.

In these two states, households

with more than one person per

room accounted for 15 to 16 percent of all households, the only

two that exceeded 10 percent. In

ten states and the District of

Columbia the percentage of crowded households surpassed the

national average of 5.7 percent; in

addition to California and Hawaii,

these included Alaska, Arizona,

Florida, Nevada, New Mexico, 

New York, Texas, and Utah.

Households in California were the

most likely to be severely crowded

(more than 1.5 persons per room).

More than half of the crowded units

in California were severely crowded

(15.2 percent crowded and 9.1 percent severely crowded). In nine

states and the District of Columbia

the percentage of severely crowded

units exceeded the national level of

2.7 percent; these were the ten listed above minus Utah.

In absolute numbers, California was

the only state with more than 1 million crowded and severely crowded

households (1.7 million crowded, 

1.0 million severely). In fact, almost

30 percent of all crowded units were

in California. California, New York,

and Texas accounted for half of all

crowded housing (6.1 million units).

Of the 2.9 million total severely

crowded units, about 36 percent

were in California alone, with almost

half in just two states — California

and Texas.

The percentage of crowded

units increased between 1990

and 2000 in most states.

Crowded housing rose from 

4.9 percent of all occupied units in

1990 to 5.7 percent in 2000. This

increase was highest in California

(12.3 percent to 15.2 percent) and

Nevada (6.4 percent to 8.6 percent).

Counties with the largest share

of their housing in mobile

homes were concentrated in

the South and the West.

Figure 8 shows mobile homes as a

percentage of each county’s housing stock. In about a dozen counties, mobile homes composed over

half the housing stock. Mobile

homes constituted about 60 percent of the housing in Long

County, Georgia, and Eureka

County, Nevada. 

The five counties with the largest

number of mobile homes were, in

numerical order: Maricopa,

Arizona; Riverside, California; Polk,

Florida; Los Angeles, California; and

Pinellas, Florida. Each of these five

counties had 50,000 or more

mobile homes. The county outside

the South or the West with the most

mobile homes was Oakland,

Michigan, at 18,000. Westmoreland, Pennsylvania, at 12,000, led

all northeastern counties in the

number of mobile homes.

Counties with the highest

proportion of crowded

households tended to be in

the West and south Texas.

Figure 9 shows counties by the percentage of occupied housing units

with more than one person per

room. Many boroughs and census

areas in Alaska with large concentrations of Alaska natives were

crowded; about half of all households in the Wade Hampton Census

Area were crowded, the highest percentage in the nation. In this county equivalent, 87 percent of occupied units had an American Indian

or Alaska Native householder.

In south Texas, about one-quarter

of all households in Zavala, Webb,

and Starr counties were crowded.

Crowding was also common in

many counties where a large proportion of the units were on

American Indian Reservations, such

as Shannon County, South Dakota

(Pine Ridge Indian Reservation) and

Apache County, Arizona (Zuni and

parts of the Fort Apache and

Navajo Reservations). Only about

477 counties or 15 percent of all

counties nationally, were at or

above the national average of 

5.7 percent crowded.

12 U.S. Census Bureau
U.S. Census Bureau 13 

Mobile Homes: 2000 Source: U.S. Census Bureau, Census 2000 Summary File 3. American Factfinder at factfinder.census.gov provides census data and mapping tools. 

U.S. p

U.S. p

Figure 8. 0 100 Miles 0 100 Miles 

0 100 Miles 

(Data based on sample. For information on confidentiality protection, sampling error, nonsampling error, and definitions, see www.census.gov/prod/cen2000/doc/sf3.pdf) 
14 U.S. Census Bureau 

Crowded Housing: 2000 Source: U.S. Census Bureau, Census 2000 Summary File 3. American Factfinder at factfinder.census.gov provides census data and mapping tools. 

U.S. p

U.S. p

Figure 9. 0 100 Miles 0 100 Miles 

0 100 Miles 

(Data based on sample. For information on confidentiality protection, sampling error, nonsampling error, and definitions, see www.census.gov/prod/cen2000/doc/sf3.pdf) 
ADDITIONAL FINDINGS

Which large cities had the

highest percentages of

crowded units?

Table 6 shows the ten places with

100,000 or more people with the

highest percentage of housing that

was crowded (more than one

person per room). Nine were in

California. In Santa Ana, East Los

Angeles, and El Monte about half

of all households were crowded,

the highest proportions of any

large cities or places. The only

place in the table not in California

was Hialeah, Florida.

Do native and foreign-born

households differ in measures

of crowding?

Households with foreign-born

householders accounted for almost

two-thirds (63.5 percent) of all

occupied units with more than 1.5

persons per room, despite making

up only a little over one-tenth

(11.4 percent) of all households

nationally. About 15.1 percent of

occupied units with a foreign-born

householder were severely crowded, as opposed to only 1.1 percent

of units with a native householder.

Occupied units with a foreign-born

householder accounted for slightly

over half (51.7 percent) of all

crowded units nationally.

In 2000, were householders

more likely or less likely to be

recent movers than in 1960?

In 1960, 22.2 percent of all householders were recent movers; in

2000, the proportion of recent

movers was 19.9 percent. For

renters, the rate stayed about the

same: 38.8 percent in 1960 and 

39 percent in 2000.

ABOUT CENSUS 2000

Why the Census Bureau collects

and tabulates structural and

occupancy data for housing.

Units in structure (from stand-alone

homes) to apartments in large

buildings serve as a basic classification of housing for many federal

programs and is analyzed along

with owner/renter status, household income, and the year the structure was built. This information is

also used by the Department of

Housing and Urban Development as

a component to set Fair Market

Rents for all areas of the country

and by the Department of Health

and Human Services to profile

housing unit types for the LowIncome Energy Assistance Program.

State and local planners use data on

units in structure to forecast the

need for services such as roads and

hospitals and to predict the number

of school-age children by using different averages of children per

household based on whether the

structure is single-family or multifamily. Federal, state, and local

planners also use this item to identify concentrations of mobile homes 

in tornado- and hurricane-prone

areas when creating emergencypreparedness plans.

Federal agencies use data on the

year the structure was built to create formulas for allocating funds,

determining substandard housing,

and constructing surveys. The

Department of Housing and Urban

Development uses this item as a

component in setting Fair Market

Rents as well in as its Community

Development Block Grant Program,

HOME, and Public Housing

Modernization allocation formulas.

The year the structure was built

helps determine, under the Older

Americans Act, the number of older

people who live in inadequate housing and who may be candidates for

home repair loans or alternative

housing. It is also used by local

areas for forecasting the need for

services such as fire protection.

Information on the year the householder moved into the unit is needed by federal agencies, such as the

Department of Health and Human

Services and the Department of

Housing and Urban Development to

calculate turnover among specified

population groups such as the elderly and minority households. This

item is also used in the development of Fair Market Rents for all

areas of the country, and to target

areas with a substantial number of

recent movers for housing and community development projects under

the Community Development Block

U.S. Census Bureau 15

Table 6.

Places of 100,000 or More With the Highest Incidence of

Crowded Units: 2000

(Data based on sample. For information on confidentiality protection, sampling error, nonsampling error, and definitions, see www.census.gov/prod/cen2000/doc/sf3.pdf)

Place Occupied

housing units

Percent

crowded

90-percent

confidence interval

Santa Ana, California.................. 72,882 50.3 49.5 - 51.1

East Los Angeles, California (CDP)* .... 29,829 48.8 47.5 - 50.1

El Monte, California ................... 27,036 47.7 46.4 - 49.0

Pomona, California.................... 37,890 34.5 33.4 - 35.6

Salinas, California .................... 38,227 32.7 31.6 - 33.8

Norwalk, California .................... 26,894 31.8 30.6 - 33.1

Oxnard, California .................... 43,630 31.2 30.2 - 32.2

Hialeah, Florida....................... 70,763 30.6 29.8 - 31.4

Garden Grove, California .............. 45,914 29.9 29.1 - 30.7

Inglewood, California . . . ............... 36,817 27.9 26.9 - 28.9

*East Los Angeles is a Census Designated Place (CDP)

Note: Because of sampling error, the estimates in this table may not be significantly different from

one another or from rates for geographic areas not listed in this table.

Source: U.S. Census Bureau, Census 2000 Summary File 3.
Grant Program. Planners also use

year-moved-into-unit data to assess

the adequacy of the housing stock

to meet shelter needs through studies of demographic and economic

data on households that have

recently moved.

Information on persons per room

is used to allocate funds for housing assistance to local governments under the Community

Development Block Grant and

Emergency Shelter Grant programs.

City and community officials use

these data to determine housing

deficiencies in neighborhoods.

This item also provides benchmark

data that measure progress toward

the Congressional goals for national housing: a decent home and

suitable living environment for

every American family.

Accuracy of the Estimates

The data contained in this report are

based on the sample of households

who responded to the Census 2000

long form. Nationally, approximately 1 out of every 6 housing units

was included in this sample. As a

result, the sample estimates may

differ somewhat from the 100-percent figures that would have been

obtained if all housing units and

people living in housing units or in

group quarters had been enumerated using the same questionnaires,

instructions, enumerators, and so

forth. The sample estimates also

differ from the values that would

have been obtained from different

samples of housing units and people living in those housing units or

in group quarters. The deviation of

a sample estimate from the average

of all possible samples is called the

sampling error. 

In addition to the variability that

arises from the sampling procedures, both sample data and 100-

percent data are subject to nonsampling error. Nonsampling error may

be introduced during any of the

various complex operations used to

collect and process data. Such

errors may include: not enumerating every household or every person in the population, failing to

obtain all required information from

the respondents, obtaining incorrect

or inconsistent information, and

recording information incorrectly.

In addition, errors can occur during

the field review of the enumerators’

work, during clerical handling of

the census questionnaires, or during the electronic processing of the

questionnaires.

Nonsampling error may affect the

data in two ways: (1) errors that are

introduced randomly will increase

the variability of the data and, therefore, should be reflected in the standard errors; and (2) errors that tend

to be consistent in one direction will

bias both sample and 100-percent

data in that direction. For example,

if respondents consistently tend to

underreport their incomes, then the

resulting estimates of households or

families by income category will

tend to be understated for the higher income categories and overstated

for the lower income categories.

Such biases are not reflected in the

standard errors.

While it is impossible to completely

eliminate error from an operation

as large and complex as the decennial census, the Census Bureau

attempts to control the sources of

such error during the data collection and processing operations.

The primary sources of error and

the programs instituted to control

error in Census 2000 are described

in detail in Summary File 3

Technical Documentation under

Chapter 8, “Accuracy of the Data,”

located at www.census.gov/prod

/cen2000/doc/sf3.pdf. 

All statements in this Census 2000

Brief have undergone statistical

testing and all comparisons are significant at the 90-percent confidence level, unless otherwise noted.

The estimates in tables, maps, and

other figures may vary from actual

values due to sampling and nonsampling errors. As a result, estimates in one category may not be

significantly different from estimates assigned to a different category. Further information on the

accuracy of the data is located at

www.census.gov/prod/cen2000

/doc/sf3.pdf. For further information on the computation and use of

standard errors, contact the

Decennial Statistical Studies

Division at 301-763-4242. 

For More Information

The Census 2000 Summary File 3

data are available from the American

Factfinder on the Internet

(www.factfinder.census.gov). They

were released on a state-by-state

basis during 2002. For information

on confidentiality protection, nonsampling error, sampling error, and

definitions, also see www.census.gov

/prod/cen2000/doc/sf3.pdf or contact the Customer Services Center at

301-763-INFO (4636).

Information on population and

housing topics is presented in the

Census 2000 Brief series, located

on the Census Bureau’s Web site at

www.census.gov/population/www

/cen2000/briefs.html. This series,

which will be completed in 2003,

presents information on race,

Hispanic origin, age, sex, household type, housing tenure, and

social, economic, and housing

characteristics, such as ancestry,

income, and housing costs.

For additional information on housing, including reports and survey

data, visit the Census Bureau’s

Internet site on at www.census.gov

/hhes/www/housing.html. To find

information about the availability

of data products, including reports,

CD-ROMs, and DVDs, call the

Customer Services Center at 

301-763-INFO (4636), or e-mail 

webmaster@census.gov.

16 U.S. Census Bureau