SOI Tax Stats - IRS Data Book: 2007

Look here for the 2007 IRS Data Book (Publications 55B), with links to the 1995 to 2000 2001 to 2003 and 2004 to 2006 IRS Data Books. The tables shown in these publications contain statistics for IRS collections and refunds, as well as number of returns. There's also information on examination activities, taxpayer assistance, chief counsel, appeals, criminal investigation, and more.
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