The Department of the Treasury manages the trust funds and provides the Social Security Administration with monthly data on financial operations of the trust funds and on investment data. Social Security has two trust funds: the Old-Age and Survivors Insurance (OASI) Trust Fund and the Disability Insurance (DI) Trust Fund.

Income & cost data
An explanation of the components of income and cost may help you better understand the data.

• Financial operations for a selected time period
• Time series for a selected component of the financial operations
• Graph shows the growth of the trust funds since 1987
• Employment taxes—technical report on the largest income component
• Benefit payments—technical report on the largest cost component

Investment data
The trust funds are invested in Federal government securities.

• Investments held at end of month, for months after 1989
• Investment transactions, for years after 1989
• Interest rate information (includes rates earned on new investments)