For Social Security and Medicare's Hospital Insurance program,
the main source of income is taxes
on wages and self-employment income. Taxes on wages are known
as FICA (Federal Insurance Contributions Act) taxes and our
FICA tax data include both employee and employer taxes. Taxes on
self-employment are sometimes referred to as SECA
(Self Employment Contributions Act) taxes.
Both FICA and SECA taxes are deposited initially on an
estimated basis, with subsequent adjustments
for actual data.
Monthly employment tax data are available for each of the
following trust funds: Social Security's Old-Age
and Survivors Insurance (OASI) or
Disability Insurance (DI) Trust Fund, or Medicare's Hospital
Insurance (HI) Trust Fund. Please note that reports of these data are
somewhat technical in nature and not all abbreviations are fully explained.