This budget process often takes an entire session of Congress; the president presents his proposals in early February, and Congress often does not finish its work on appropriations bills until September (and sometimes even later). The federal government's chief source of funds to cover its expenses is the income tax on individuals, which in 1999 brought in about 48 percent of total 86

federal revenues. Payroll taxes, which finance the Social Security and Medicare programs, have become increasingly important as those programs have grown. In 1998, payroll taxes accounted for one-third of all federal revenues; employers and workers each had to pay an amount equal to 7.65 percent of their wages up to $68,400 a year. The federal government raises another 10 percent of its revenue from a tax on corporate profits, while miscellaneous other taxes account for the remainder of its income. (Local governments, in contrast, generally collect most of their tax revenues from property taxes. State governments traditionally have depended on sales and excise taxes, but state income taxes have grown more important since World War II.) The federal income tax is levied on the worldwide income of U.S. citizens and resident aliens and on certain U.S. income of non-residents. The first U.S. income tax law was enacted in 1862 to support the Civil War. The 1862 tax law also established the Office of the Commissioner of Internal Revenue to collect taxes and enforce tax laws either by seizing the property and income of non-payers or through prosecution. The commissioner's powers and authority remain much the same today. The income tax was declared unconstitutional by the Supreme Court in 1895 because it was not apportioned among the states in conformity with the Constitution. It was not until the 16th Amendment to the Constitution was adopted in 1913 that Congress was authorized to levy an income tax without apportionment. Still, except during World War I, the income tax system remained a relatively minor source of federal revenue until the 1930s.