Notes: With the 2004 estimates, the Centers for Medicare and Medicaid Services (CMS) incorporated new concepts, methods, and data sources in the National Health Expenditure Accounts and revised the entire time series back to 1960. According to CMS, the most important revisions were the introduction of estimates of investment in medical equipment and software, expanded estimates of investment in medical-sector structures, and the use of updated data from the U.S. Census Bureau’s 2002 Economic Census and other sources. Overall, these changes raised the estimates of health spending 3-4% for nearly all years prior to 2004.

Source: Centers for Medicare and Medicaid Services, Office of the Actuary, National Health Statistics Group, at http://www.cms.hhs.gov/NationalHealthExpendData/ (see Historical; NHE summary including share of GDP, CY 1960-2004; file nhegdp04.zip).