APPENDIX

Appendix 1 : DATA SOURCES

A.1.1. Internal Revenue Service and Statistics of Income

All income levels of the top deciles were derived from the Statistics of Income (SOI). Listed below are the various publications the SOI tables were released in, along with a couple of comments on the data availability when necessary.

1913-1915: "Annual Report of the Commissioner of Internal Revenue". The 1913, 1914, and 1915 tables provide the number of tax returns by size of income and by state. However, the dollar amount of the state total income accruing to each of the income classes was not released.

1916-1973, 1975-1981: "SOI Individual Income Tax Returns" of Tax Year n, Publication 79 (8-83), Basic Tables, Part 4 (State Data), first and last tables.

1944: State data are published by composition of income, but not by income-class interval (only U.S. aggregates are available by income class).

1974: U.S. Department of the Treasury, IRS “Supplemental Statistics of Income. Small Area Data, Individual Income Tax Returns”, 1974. Publication 1008 (12-77). Basic Table 3 ‘Selected Income and Tax Items by Size of Adjusted Gross Income and by State and County’, pp. 60-436.

Between 1982 and 1987, the IRS interrupted the regular publications of state data by size of adjusted gross income (AGI). This interruption apparently corresponds to a change in methodology from sample estimation to master file computerization. Only the national aggregate by size of AGI is found in the “SOI Bulletin” of Tax Year n + 2, Fall, Publication 1136, “Selected Statistical Series”, Table 2 ‘Individual Income and Tax by State, [Year n]’. The substitute data for these six years were found in the following issues:

1982: “SOI Bulletin”, Volume 5, Number 1, Summer 1985, ‘Individual Income by Zip Code Area, 1979 and 1982’.

1983: “Statistics of Income, Individual Tax Model for 1983”, IRS.

1984-1985: Bureau of the Census annual data extracted from the March Current Population Survey, household count for 21 income-class intervals for each state.

1986-1987: “SOI Bulletin”, Volume 10, Number 2, Fall 1990, ‘Individual Income Tax Return Data by State, 1986-1988’.

1988-1996: “SOI Bulletin” of Tax Year n + 2, Fall, Publication 1136, ‘Selected Historical Data’ (yellow), Table 2 ‘Individual Income and Tax Data by State and Size of AGI, [Year n]’.

1997-2003: Data by state, by income size, and by income sources are available on the IRS website.