Because of the significance of Internal Revenue Service (IRS) revenue collections to federal receipts &, in turn, to the consolidated financial statements of the U.S. Government, which the General Accounting Office (GAO) is required to audit, and Congress's interest in financial management at IRS, GAO audits IRS's financial statements annually to determine whether: (1) the financial statements IRS prepares are reliable, (2) IRS management maintained effective internal controls, and (3) IRS complies with selected provisions of significant laws and regulations and its financial systems comply with the Federal Financial Management Improvement Act (FFMIA). Charts and tables.