Expenditures in the United States federal budget

The United States federal budget contains a number of expenditures, which include mandatory programs such as the Medicare and Social Security programs, military spending, and discretionary funding for Cabinet Departments (e.g., United States Department of Justice) and agencies (e.g., Securities & Exchange Commission).

During FY2014, the federal government spent $3.504 trillion on a budget or cash basis, up $50 billion or 1% vs. FY2013 spending of $3.455 trillion. Major categories of FY 2014 spending included:

Expenditures are classified as mandatory, with payments required by specific laws, or discretionary, with payment amounts renewed annually as part of the budget process. Expenditures averaged 20.4% GDP over the past 40 years, generally ranging +/-2% GDP from that level. The 2014 spend was 20.3% GDP, versus 2013 spend of 20.8% GDP and a recent 2009 peak of 24.4% GDP.

Discretionary spending requires an annual appropriation bill, which is a piece of legislation. Discretionary spending is typically set by the House and Senate Appropriations Committees and their various subcommittees. Since the spending is typically for a fixed period (usually a year), it is said to be under the discretion of the Congress. Some appropriations last for more than one year (see Appropriation bill for details). In particular, multi-year appropriations are often used for housing programs and military procurement programs.

Direct spending, also known as mandatory spending, refers to spending enacted by law, but not dependent on an annual or periodic appropriation bill. Most mandatory spending consists of entitlement programs such as Social Security benefits, Medicare, and Medicaid. These programs are called "entitlements" because individuals satisfying given eligibility requirements set by past legislation are entitled to Federal government benefits or services. Many other expenses, such as salaries of Federal judges, are mandatory, but account for a relatively small share of federal spending.

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