The analysis utilized four different surveys collected by the federal government. The unit of analysis differs among them. A brief description of the four surveys follows.
The Survey of Consumer Finances
Most of the analysis of debt and assets is based on the Survey of Consumer Finances. The SCF is collected every three years and is sponsored by the Board of Governors of the Federal Reserve System in cooperation with the U.S. Department of the Treasury. The interviews are conducted roughly between May and December. Aside from the detailed information on the assets and liabilities of the household, the SCF has detailed demographic information on the head of the household. While other sources exist on trends in aggregate indebtedness, the SCF is the foremost source of information on which demographic groups have particular kinds of outstanding liabilities. Bricker et al. (2012) is a good introduction to the survey. Prior analyses of young adult indebtedness have also utilized the SCF (Chiteji, 2007).
The most recent SCF available is for 2010. The tabulations presented are based on the public use version of the SCF available on the Federal Reserve’s website: http://www.federalreserve.gov/econresdata/scf/scfindex.htm. The SCF sample typically consists of approximately 4,500 households. The 2010 data have 6,482 unweighted households in the survey, of which 1,178 were households younger than 35. The 1983 SCF had a sample size of 4,098, of which 1,152 were headed by young adults.
The definition of a “household” in the SCF differs from that used in Census Bureau studies. The sampling unit in the SCF is the “primary economic unit” (PEU), not the household. As stated by the Federal Reserve Board, “the PEU consists of an economically dominant single individual or couple (married or living as partners) in a household and all other individuals in the household who are financially interdependent with that individual or couple.” Federal Reserve Board publications refer to the PEU as a “family,” but readers may infer that this necessitates the presence of two related persons, though a PEU can consist of a person living alone. In this document, a PEU is referred to as a “household.”
American Housing Survey
The analysis of recent mover households utilized the American Housing Survey. The AHS is conducted by the Census Bureau and sponsored by the U.S. Department of Housing and Urban Development. The national data survey has been collected every odd-numbered year, and 2011 is the most recent available national data. The survey started in 1973 and has had the same core sample since 1985.
Several Census data sets provide information on occupied and vacant housing units and provide information on national homeownership rates. Data sets such as the American Community Survey and Current Population Survey also shed light on household mobility, in that they inquire as to whether the respondent resided in the same residence one year ago or five years ago. Those responding “different house” are asked the location of the prior residence and hence these surveys shed light on geographic mobility. The American Community Survey and Current Population Survey do not inquire as to the previous ownership of the dwelling or tenure (whether the household was owner-occupied versus renter-occupied).
The American Housing Survey interviews are conducted over several months. For example, the 2011 AHS conducted interviews between July and December of 2011.
The tabulations published herein are derived from the public microdata files available from HUD: http://www.huduser.org/portal/datasets/ahs.html. The tabulations very closely approximate the national summary tables published by the HUD.
Matching the tabulations on recent movers published in the summary report, “recent movers” refers to householders who moved during the year prior to the month of interview and moved from within the United States. The structure of the previous residence must have been a house, apartment or manufactured/mobile home.
The number of households surveyed has increased since the 2001 survey. In the 2001 survey the nation’s occupied households are represented by 47,852 unweighted households. Recent movers are captured by 6,072 unweighted households, of which 3,262 were young adult recent movers.
American Community Survey
Analysis of the living arrangements of persons and homeownership rates is based on the U.S. Census Bureau’s American Community Survey. The ACS is the largest household survey in the United States, with a sample of about 3 million addresses. It covers the topics previously covered in the long form of the decennial census. The ACS is designed to provide estimates of the size and characteristics of the resident population, which includes persons living in households and group quarters. Further information on the ACS can be found at http://www.census.gov/acs/www/about_the_survey/american_community_survey/.
The tabulations are based on the one-year 2001 and 2011 ACS files. The specific files analyzed were the Integrated Public Use Microdata Series (IPUMS) provided by the University of Minnesota.8
To most closely match the universes in the other data sets, the ACS analysis is restricted to adults residing in households. The sample size in the ACS has increased over time, but even in 2001 it was very large. The number of unweighted adults in the 2001 ACS residing in households was 896,036, of whom 239,920 were younger than 35.
Homeownership rates are based on analysis of households, not adults. Nonetheless, the unweighted counts of households in the ACS are quite large. In the 2001 ACS there are 93,892 households headed by those younger than 35. By single year of age of the head, the fewest number of cases in the 2001 ACS were those headed by 18-year-olds. In the 2001 ACS there were 545 unweighted households headed by an 18-year-old.
Consumer Expenditure Survey
Automobile ownership rates are derived from the Consumer Expenditure Survey, conducted by the U.S. Census Bureau for the Bureau of Labor Statistics. The goal of the CE survey is to collect data on the buying habits of American consumers. The current form of the survey dates to 1980, but it has undergone revisions in the interim that affect the comparability of data over time. The survey has two components—a quarterly Interview Survey and a weekly Diary Survey, each with its own questionnaire and sample. In the Interview Survey, families in the sample are interviewed every three months over five calendar quarters. Respondents to the Diary Survey maintain a detailed record of expenditures for two consecutive weeks. At the present time, the Interview and Diary components collect completed surveys from approximately 7,000 housing units each.
The expenditure data are collected and reported for “consumer units.” A consumer unit consists of any of the following: (1) All members of a particular household who are related by blood, marriage, adoption, or other legal arrangements; (2) a person living alone or sharing a household with others or living as a roomer in a private home or lodging house or in permanent living quarters in a hotel or motel, but who is financially independent; or (3) two or more persons living together who use their incomes to make joint expenditure decisions.
Further information on the CE can be found at http://www.bls.gov/cex/home.htm#publications.
The auto ownership rates are from the published current expenditure tables at http://www.bls.gov/cex/home.htm#tables.