The American Housing Survey (AHS) is conducted every odd-numbered year for the Nation as a whole, and surveys for 47 individual metropolitan areas are conducted every 4 to 6 years in the even-numbered years. The AHS has been a joint effort of the Department of Housing and Urban Development and the Census Bureau since 1973. AHS national surveys provide information about U.S. housing throughout the 10-year time span between the decennial censuses. Not only is the AHS more current and more frequent than the decennial census, but the information it collects is more comprehensive.

AHS surveys collect information on the Nation’s entire housing stock. Data gathered for each housing unit include structural characteristics such as size, number of rooms, plumbing, amenities, housing quality, and household equipment (heating, for example); the neighborhood in which it is located; financing and housing costs; demographic information such as household composition, race/ethnicity, income, migration, and householder’s gender; and occupancy and tenure of the housing unit. The national survey is conducted through telephone interviews or personal visits to approximately 60,000 housing units every 2 years, whereas each metropolitan survey generally involves interviews or visits covering up to 5,000 housing units every 4 to 6 years. A unique and important aspect of the AHS is that the same housing units are revisited during each survey, chronicling the history of America’s housing. Newly constructed housing units are added each survey year so that the survey represents all housing in the United States.

Results from the 2001 national survey will be available soon. These data are the basis for this article, which presents selected results from the 2001 survey that describe the housing of American families in 2001. Estimates contained in this article are preliminary and could change as file processing is completed. Furthermore, because the AHS is a sample, the estimates are subject to sampling variability. This article also explains the many ways to access this rich data source. The 2002 metropolitan surveys are now being conducted in 13 areas—Anaheim, Buffalo, Charlotte, Columbus, Dallas, Fort Worth, Kansas City, Miami, Milwaukee, Phoenix, Portland, San Bernardino, and San Diego—and the data will be available in spring 2003.

Selected Housing and Family Information From the 2001 National AHS

The American housing stock consists of nearly 120 million housing units, of which approximately 12 million are vacant or for seasonal use. According to AHS data, American families are homeowners by a ratio of 2 to 1; generally live in single-family housing; occupy fairly new homes; live in suburbs of metropolitan areas; live in homes that have between four and six rooms, three or more bedrooms, one or more complete bathrooms, and few deficiencies; and pay approximately 20 percent of their income toward housing costs.

Table 1. Composition of the Housing Stock

Housing Type	Units	Percentage
All	119,120,000	100.0
Year round	117,080,000	98.3
Total occupied	106,407,000	89.3
Owner occupied	72,365,000	60.7
Renter occupied	34,042,000	28.6
Vacant	11,712,000	9.8
Seasonal	2,040,000	1.7

The AHS can be used to gain more insight into how Americans are housed; the 2001 data is being made available and has been used to develop the following overview of the housing of American families in 2001.¹

The composition of America’s housing stock is shown in table 1. America’s housing stock was estimated to be 119,120,000 units in 2001, up 3.4 percent from the 115,253,000 estimated in the 1999 AHS. Of these units almost all (98.3 percent) were suitable for year-round use, and nearly 10 percent were vacant. Of the 106,410,000 occupied units, 68 percent were owner occupied. The homeownership rate has increased from 66.9 percent in 1999.

Table 2 shows that the predominant type of American housing is the single-family unit, which accounts for 76 percent of the Nation’s housing stock. The most popular single-family unit is the detached unit, accounting for 73.3 million housing units (61.5 percent of the stock), followed by a manufactured (mobile) home (8.8 million housing units, or 7.4 percent of the stock) and an attached unit (8.5 million, or 7.1 percent of the stock).

Table 2. Housing Stock by Type

Type of Housing Unit	Units	Percentage
Single-family detached	73,306,000	61.5
Single-family attached	8,487,000	7.1
Multifamily	28,486,000	23.9
2–4 units	9,334,000	7.8
5–9 units	5,736,000	4.8
10–19 units	5,374,000	4.5
20–49 units	3,918,000	3.3
50 or more units	4,124,000	3.5
Manufactured (mobile)	8,837,000	7.4

Approximately 28 million housing units, or 24 percent of the total housing stock, are in multifamily buildings. The most prevalent multifamily size category is the 2- to 4-unit building, which comprises approximately one-third of all multifamily units. Approximately 4.1 million housing units are in large multifamily structures and represent approximately 15 percent of the multifamily housing stock.

As shown in table 3, the American housing stock is fairly new. Approximately 30 percent of the units have been built since 1980, and the median construction date is 1970. This median means that half of the housing units have been built within the past 30 years. Houses are also fairly durable; 9.8 million units (8.2 percent of all housing units) were built in 1919 or earlier and are more than 80 years old.

Table 3. Year Structure Built

Year Built	Units	Percentage
2000–01	3,118,000	2.6
1995–99	8,884,000	7.5
1990–94	7,205,000	6.0
1985–89	8,879,000	7.5
1980–84	7,663,000	6.4
1975–79	12,010,000	10.1
1970–74	11,518,000	9.7
1960–69	15,944,000	13.4
1950–59	13,766,000	11.6
1940–49	8,263,000	6.9
1930–39	6,565,000	5.5
1920–29	5,492,000	4.6
Pre-1919	9,810,000	8.2

Table 4 shows that housing is generally located in metropolitan areas (91.1 million units, or 76.5 percent of the stock). Within metropolitan areas, approximately two-thirds of these units are located in suburban areas outside central cities. Housing units located outside metropolitan areas account for nearly one-fourth (23.5 percent) of American housing. Although these proportions have changed very little from what was reported in the 1999 AHS, there have been shifts within metropolitan areas: Central cities were down 0.9 percentage point, and the suburban rate increased by 1.3 percentage points.

Regionally, the South had the greatest number (43.6 million) and percentage (36.6 percent) of housing units. The Northeast had the fewest with 22.3 million units, or 18.8 percent of all housing units. These percentages are little changed from the 1999 AHS and show minimal decreases in the Northeast (0.6 percentage point) and Midwest (0.4 percentage point), and increases in the South (0.6 percentage point) and the West (0.4 percentage point).

Table 4. Location

Location	Units	Percentage
Metropolitan	91,139,165	76.5
Inside central cities	35,076,918	29.4
Suburban	56,062,247	47.1
Outside metropolitan areas	27,977,352	23.5
Northeast region	22,347,303	18.8
Midwest region	27,747,660	23.3
South region	43,571,170	36.6
West region	25,450,384	21.4

Table 5 shows the distribution of housing units by number of rooms per housing unit. The greatest number of housing units (27.9 million, or 23.4 percent) had 5 rooms; slightly fewer housing units have either 4 rooms (23.1 million, or 19.4 percent) or 6 rooms (24.7 million, or 20.7 percent.) The size distribution of housing has not changed much from what was reported in the 1999 AHS.

Table 5. Number of Rooms

Rooms	Units	Percentage
1	613,000	0.5
2	1,392,000	1.2
3	10,703,000	9.0
4	23,057,000	19.4
5	27,877,000	23.4
6	24,658,000	20.7
7	14,715,000	12.4
8	8,465,000	7.1
9	3,913,000	3.3
10 or more	3,724,000	3.1

Nearly 69 million American homes (57.8 percent) have three or more bedrooms; housing units containing three bedrooms are most popular and account for 48.4 million (40.6 percent) of all housing units (see table 6). Approximately 1.2 million housing units (1 percent) do not have a separate bedroom. The distribution is nearly unchanged from 1999 AHS results. Virtually all housing units (99.5 percent) have bathrooms; only 617,000 households report having no bathrooms. Nearly 50 million households have one complete bathroom and nearly 52 million have two or more bathrooms—a slight increase in the number of bathrooms reported in the 1999 AHS. (See table 7.)

Table 6. Number of Bedrooms

Bedrooms	Units	Percentage
None	1,216,000	1.0
1	14,479,000	12.2
2	34,616,000	29.1
3	48,374,000	40.6
4 or more	20,433,000	17.2

Table 7. Number of Bathrooms

Bathrooms	Units	Percentage
None	617,000	0.5
1	49,824,000	41.8
1.5	16,819,000	14.1
2 or more	51,857,000	43.5

American housing units have few deficiencies—especially within owner-occupied units. Table 8 shows the incidence of selected deficiencies for all occupied housing units and then distinguishes between owner- and renter-occupied housing units. Of the approximately 106 million occupied units in the United States, only 1.1 million had holes in the floors; the incidence was lower for owner-occupied units (0.8 percent) than for renter-occupied units (1.8 percent). Open cracks or holes in interior walls are more prevalent—5.7 million occupied units reported this deficiency—and the incidence for renters (8.3 percent) is more than twice that of owners (4.0 percent). Electrical deficiencies are very rare: Only 71,000 households reported no electrical wiring, and 547,000 reported exposed wiring. The lack of electrical outlets in one or more rooms occurs in 1.3 million homes, and this deficiency, although uncommon for both renters and owners, is seen nearly twice as often in rental units. Compared with the 1999 AHS results, the prevalence of deficiencies is down slightly.

AHS interviewers include monthly housing costs in their surveys; distribution of these costs is shown in table 9. Housing costs for renters include contract rent, property insurance, and utilities; housing costs for owners include mortgage (contract for sale or installment loan) payments, property insurance, real estate taxes, fees (association, condominium, or cooperative), park fees for mobile homes, land rents, routine maintenance, and utilities. Table 9 tabulates the results for all households, renters, and owners. For all housing units, the median monthly housing cost is $675 per month, with owners having a monthly median housing cost of $724 and renters having a monthly median housing cost of $627. Median housing costs vary significantly among regions. The South has the lowest median housing cost ($594), the Midwest has the second lowest ($620), the Northeast has the second highest ($745), and the West has the highest median monthly housing cost ($832). A higher percentage of owners (13.9 percent) had housing costs of $1,500 or more per month compared with renters (3.7 percent). At the lower end of the distribution, we see that approximately 19 percent of owners had monthly costs of under $300, and this may be explained by the fact that nearly 4 out of 10 owners have no mortgage debt and therefore no monthly mortgage expenses. Table 9 also shows that nearly 2 million households paid no cash rent for their housing units. Although absolute monthly housing costs indicate that renters pay less than owners, the situation reverses when these absolute magnitudes are converted to fractions of income spent on housing. Overall, the median housing cost burden (proportion of income spent on housing) is 20.3 percent, but the burden rate is 26.5 percent for renters and 17.6 percent for owners. As might be expected, housing costs increased by approximately 15 percent from what was reported in the 1999 AHS.

Table 8. Selected Housing Deficiencies

	All		Owner Occupied		Renter Occupied
Deficiency	Number of Units	Percentage	Number of Units	Percentage	Number of Units	Percentage
Holes in floors	1,148,000	1.1	546,000	0.8	602,000	1.8
Open cracks or holes (interior)	5,713,000	5.4	2,898,000	4.0	2,814,000	8.3
Broken plaster or peeling paint (interior)	2,723,000	2.6	1,284,000	1.8	1,439,000	4.2
No electrical wiring	71,000	0.1	64,000	0.1	7,000	0
Exposed wiring	547,000	0.5	304,000	0.4	244,000	0.7
Rooms without electrical outlets	1,320,000	1.2	713,000	1.0	607,000	1.8

Table 9. Monthly Housing Costs

	All		Owner Occupied		Renter Occupied
Payment ($)	Number of Units	Percentage	Number of Units	Percentage	Number of Units	Percentage
All	106,407,000	100.0	72,365,000	100.0	34,042,000	100.0
No cash rent	1,949,000	1.8	NA	NA	1,949,000	5.7
Less than 100	1,284,000	1.2	814,000	1.1	470,000	1.4
100–199	6,311,000	5.9	4,980,000	6.9	1,331,000	3.9
200–249	4,860,000	4.6	4,033,000	5.6	828,000	2.4
250–299	4,818,000	4.5	3,958,000	5.5	861,000	2.5
300–349	4,800,000	4.5	3,711,000	5.1	1,089,000	3.2
350–399	4,629,000	4.4	3,208,000	4.4	1,421,000	4.2
400–449	4,675,000	4.4	2,775,000	3.8	1,900,000	5.6
450–499	4,449,000	4.2	2,387,000	3.3	2,063,000	6.1
500–599	9,616,000	9.0	4,882,000	6.7	4,734,000	13.9
600–699	8,955,000	8.4	4,382,000	6.1	4,573,000	13.4
700–799	7,775,000	7.3	4,097,000	5.7	3,678,000	10.8
800–999	12,253,000	11.5	7,680,000	10.6	4,573,000	13.4
1,000–1,249	9,794,000	9.2	7,467,000	10.3	2,327,000	6.8
1,250–1,499	6,776,000	6.4	5,790,000	8.0	985,000	2.9
1,500+	13,463,000	12.7	12,203,000	16.9	1,260,000	3.7

The tables presented in this article have only skimmed the surface of the information available from the AHS. The hard-copy report will contain nearly 500 pages of detailed tables about America’s housing units. In addition to chapters on all housing units and occupied housing units, there are separate chapters for owner-occupied units, renter-occupied units, African-American households, Hispanic households, and elderly households. Each chapter contains a set of up to 25 tables covering general housing characteristics; height and condition of the buildings; size of the units and lots; equipment and plumbing; fuels; housing quality indicators; neighborhood; household composition; recent movers; reasons for moving; income; housing costs; value, price, and source of downpayments; rooms; square footage; detailed tenure; income details; detailed housing costs; value; structure type and climate; journey to work; and units in structure. In addition, the microdatabase can be used to create customized or user-specified tables and to perform multivariate analyses. In the next section, we discuss the many ways of accessing this rich source of housing data.

Accessing Housing Information

HUD and the Census Bureau have given high priority to making the AHS accessible. Users may download AHS information in tabular and microdata formats. A full array of media is used; the tabulations are available in hard copy, PDF, CD-ROM, and downloadable Internet files, and the microdata files (in ASCII or SAS formats) are available on CD-ROM or are downloadable from the Internet. Copies of the printed versions are available from HUD USER (1–800–245–2691). The national AHS reports can be purchased from the Government Printing Office (202–512–1800), and the metropolitan area reports can be obtained from the Census Bureau (301–457–4100). Both the Census Bureau and HUD maintain Internet sites, and HUD operates an AHS listserv for the AHS user community.

The HUD Web site for the AHS is www.huduser.gov/datasets/ahs.html. The following will be posted as they become available:

• The 2001 microdata files for downloading in both SAS and ASCII formats.

• Summary statistics for the 2001 AHS.

• Line-by-line comparisons of 1995, 1997, and 1999 estimates and the 2001 initial estimates for a wide array of housing and occupant characteristics.

• The new codebook for the survey. This has been entirely rewritten and released as a PDF file. It will include the 2001 dataset by the time the public-use file is released.

• Links to the Census Bureau Web site.

• Microdata in downloadable format for the 1995, 1997, 1999, and 2001 national surveys and the 1995, 1996, and 1998 metropolitan surveys.

• Information for ordering reports and documents from HUD USER (P.O. Box 23268, Washington, D.C. 20026-3268).

The Census Web site for the AHS is www.census.gov/hhes/www/ahs.html. This site provides:

PDF versions of AHS national and metropolitan reports from 1975 through 1999. The 2001 national report will be added as soon as it is released. Other AHS and housing reports are also available.

Internet access to the microdata files for extracts and analyses using automated systems. The 1997, 1999, and 2001 (forthcoming) national and 1998 metropolitan surveys are available through the FERRET system, which allows users to download SAS datasets and ASCII extracts. User-specified tables can also be created through FERRET. The 1993 and 1995 national surveys are available for extracting and downloading through the Data Extraction System.

A description of the surveys, historical changes in the surveys, definitions of concepts and variables, sample design and sizes, estimation weights, and survey results in brief formats.

Information for ordering reports and documents from Customer Services (Census Bureau, Washington, DC 20233–8500).

HUD operates an Internet mailing list to provide information and to create a forum for exchange of information within the AHS user community. Subscription instructions can be found at http://www.huduser.gov/portal/subscribe/subscribe.html.

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