The United States raises less tax revenue as a percentage of gross domestic product (GDP) than most other countries in the Organization for Economic Co-operation and Development (OECD). In 2003, taxes in the United States, including all levels of government, amounted to 25.6 percent of GDP, compared with 33.9 percent for other countries in the Group of 7 (G7) and 34.7 percent for non-G7 OECD countries. The United States raises more personal income tax and property tax as a share of GDP than other OECD countries, but less corporate income tax, Social Security contributions, and taxes on goods and services.