Access Restrictions:
Tables include historical data, but how far back varies from table to table. Some data can go back as far as 1878, other data just to 1990. Tables are updated as new data are issued. Downloadable spreadsheets are as current as possible; the pdf version is not as current as it is updated annually to conform with the print version of the Statistical Abstract.
Some tables with historical data may present historical data points for every five or ten years, plus several years of more current data. If you need to see data for individual years, you can look at the digital archive of the Statistical Abstract on the US Census Bureau website.