Income inequality (as measured by Gini index), by type of income measured, 1979–2007

Market income Market income plus transfers minus federal taxes (actual) Market income plus transfers minus federal taxes (holding 1979 progressivity)
1979 0.479 0.367 0.366914
1980 0.486 0.371 0.372276
1981 0.489 0.379 0.374574
1982 0.497 0.391 0.380702
1983 0.509 0.407 0.389894
1984 0.511 0.415 0.391426
1985 0.516 0.422 0.395256
1986 0.537 0.444 0.411342
1987 0.524 0.42 0.401384
1988 0.536 0.436 0.410576
1989 0.529 0.43 0.405214
1990 0.525 0.426 0.40215
1991 0.524 0.419 0.401384
1992 0.534 0.427 0.409044
1993 0.535 0.421 0.40981
1994 0.537 0.419 0.411342
1995 0.537 0.42 0.411342
1996 0.547 0.433 0.419002
1997 0.554 0.445 0.424364
1998 0.553 0.447 0.423598
1999 0.558 0.454 0.427428
2000 0.572 0.469 0.438152
2001 0.554 0.446 0.424364
2002 0.554 0.442 0.424364
2003 0.561 0.448 0.429726
2004 0.575 0.465 0.44045
2005 0.589 0.479 0.451174
2006 0.59 0.483 0.45194
2007 0.59 0.489 0.45194

Note: The Gini index is a commonly used measure of inequality, ranging from 0 (perfectly equitable income distribution) to 1 (perfectly inequitable income distribution).

Source: Author's analysis of CBO (2011)

View the underlying data on epi.org.