Detailed Household Income Share Background

The Census Bureau has implemented a number of changes in collection, categories, and methods since 1967. These include:

• Starting in 2003, respondents were allowed to choose one or more races; for the year 2002 and earlier, respondents could report only one race group
• Black alone refers to people who reported Black and did not report any other race category; before 1967, data are for "Black and other races" combined
• Asian alone refers to people who reported Asian and did not report any other race category
• People of Hispanic origin may be of any race
• 1967 data reflect implementation of a new March CPS processing system.
• 1971 data reflect introduction of 1970 census-based sample design and population controls
• 1972 data reflect full implementation of 1970 census-based sample design
• 1974 data reflect the implementation of a new processing system including 11 income questions
• 1974 and 1975 data contains some estimates that were derived using Pareto interpolation and may differ from earlier published data that were derived using linear interpolation
• First year median data in 1976 were derived using both Pareto and linear interpolation; before this year, all medians were derived using linear interpolation
• 1979 data reflect implementation of 1980 census population controls; the questionnaire was expanded to show 27 possible values from 51 possible sources of income
• 1983 data reflect implementation of Hispanic population weighting controls and introduction of 1980 census-based sample design
• 1985 reflects the full implementation of the 1980 Census re-design; also, amount for earnings from longest job were increased to $299,999
• 1987 data reflect implementation of a new March CPS processing system
• 1992 data reflect implementation of 1990 census population controls
• 1993 data reflect a change from from paper and pencil to computer-assisted interviewing; also, the March 1994 income supplement was revised to allow for the coding of different income amounts on selected questionnaire items
• 1994 data reflect introduction of 1990 census-based sample design
• 1995 data reflect full implementation of the 1990 census-based sample design and metropolitan definitions, 7,000 household sample reduction, and revised race edits
• Starting in 1999, alternative income definition number 7 includes federal EIC and EIC for the nine states (Iowa, Kansas, Massachusetts, Maryland, New York, Oregon, Rhode Island, Vermont, and Wisconsin) that use federal eligibility rules to compute the state credit as a percentage of the federal EIC
• Starting in 1999, 50th percentile is based on micro-sorted data
• 1999 data reflect the implementation of Census 2000-based population controls
• 2000 data reflect the implementation of a 28,000 household sample expansion
• 2004 data have been revised to reflect a correction to the weights in the 2005 ASEC [define]
• Beginning with 2009 income data, the Census Bureau expanded the upper income interval used to calculate medians and Gini indexes to $250,000 or more
• 2010 data include the implementation of Census 2010-based population controls.