The term baseline means a projection of the level of spending and receipts, and certain other budget levels, that will occur, generally in a fiscal year and a period of time following that fiscal year, without any change in existing policy. Proposed legislation is measured against these projections to determine to what extent its enactment would change these spending and receipt amounts.
For the Congressional Budget process, the baseline is defined by section 257 of the Balanced Budget and Emergency Deficit Control Act of 1985. While on that Act’s enactment it was placed within section 251, it was subsequently transferred to section 257 by the Budget Enforcement Act of 1990.
See section 257 (BBECA).
CBO Glossary of Budgetary and Economic Terms (July 2016)
baseline: An estimate of spending, revenues, the deficit or surplus, and the public debt expected during a fiscal year that reflects the assumption that current laws will generally remain unchanged. The baseline is a benchmark for measuring the budgetary effects of proposed changes in revenues and spending. It incorporates the assumption that, in general, receipts and mandatory spending will continue or expire in the future as required by law and that the future funding for discretionary programs will equal the most recently enacted appropriation, adjusted for inflation but constrained by limits established in law on discretionary appropriations. (Limits on such discretionary programs that were defined in the Balanced Budget and Emergency Deficit Control Act of 1985 were reinstated by the Budget Control Act of 2011. Those limits last through 2021.) Rules governing the baseline are specified in section 257 of the Deficit Control Act. Cost estimates consistent with section 257 are used by the House and Senate Budget Committees in implementing the pay-as-you-go rules in each House and are required for estimates under the Statutory Pay-AsYou-Go Act of 2010. See discretionary spending limits (or caps) and pay-as-you-go.
GAO Glossary of Terms and Definition (September 2005)
An estimate of spending, revenue, the deficit or surplus, and the public debt expected during a fiscal year under current laws and current policy. The baseline is a benchmark for measuring the budgetary effects of proposed changes in revenues and spending. It assumes that receipts and mandatory spending will continue or expire in the future as required by law and that the future funding for discretionary programs will equal the most recently enacted appropriation, adjusted for inflation. Under the Budget Enforcement Act (BEA), which will expire at the end of fiscal year 2006, the baseline is defined as the projection of current-year levels of new budget authority, outlays, revenues, and the surplus or deficit into the budget year and outyears based on laws enacted through the applicable date. (See also Projections.)
Projected levels of governmental receipts (revenues), budget authority, and outlays for the budget year and subsequent fiscal years, assuming generally that current policies remain the same, except as directed by law. The baseline is described in the Congressional Budget Office’s (CBO) annual report for the House and Senate Budget Committees, The Budget and Economic Outlook, which is published in January. The baseline, by law, includes projections for 5 years, but at the request of the Budget Committees, CBO has provided such projections for 10 years. In most years the CBO baseline is revised in conjunction with CBO’s analysis of the President’s budget, which is usually issued in March, and again during the summer. The “March” baseline is the benchmark for measuring the budgetary effects of proposed legislation under consideration by Congress.
CRS Report – Baselines and Scorekeeping in the Federal Budget Process (November 26, 2012)
Balanced Budget and Emergency Deficit Control Reaffirmation Act of 1987
Bases of Budgeting