Taxpayers in the top 1 percent of adjusted gross income reported adjusted gross income of at least $388,806 for 2006 and accounted for 39.9 percent of the total income tax reported. Taxpayers in the top 5 percent of adjusted gross income reported adjusted gross income of at least $153,542 for 2006 and accounted for 60.1 percent of the total income tax reported.

(Source: Internal Revenue Service, Statistics of Income Bulletin, Winter 2010, Washington D.C.)

Of the 6,623,900 corporate income tax returns filed for 2007, 4,155,800 or 63 percent were S corporation returns. The number of partnership returns filed for 2007 was 3,147,000.

(Source: Internal Revenue Service, Statistics of Income Bulletin, Summer 2010, Historic Table 21, Washington D.C.)