Historical Statistics of the United States
This online version of the "Millennial Edition" of a classic compendium of U.S. Statistics is the electronic equivalent of a five volume set--which Sawyer Library also owns--that provides U.S. statistics from colonial times to the near present. (End dates vary from table to table, but this resource is most useful for the deep historical data and is not the best source for current statistics.) HSUS covers topics like population, work and welfare, economic structure and performance, economic sectors, and governance and international relations. Want to find a table of "Population of Massachusetts, by age, sex, race, and ethnicity: 1764–1784"? You can find it here. And you can download tables in Excel or CSV (look for use and download options in the upper right of any table screen.) Sadly, searching the content of the online version can be frustrating, so keep in mind that for browsing, you might be better served by the print version.