The IRS’s Statistics of Income Division has released 2005 Corporation Income Tax Returns:

Data tables included in the 2005 Corporation Complete Report are available. This report presents data on corporation income tax returns with accounting periods that ended July 2005 through June 2006. Data have been classified in various ways, including by form type, industry, size of total assets, and size of business receipts. A separate section of the publication presents data tables for S corporations. Supporting text is also available, including an introduction that highlights changes, an explanation of terms, description of the sample, and changes in the law.