Statistics by/about the US
American FactFinder/ US Census Bureau: Provides access to US Census data about the United States, Puerto Rico and the Island Areas. Contains statistical demographic and economic information about the United States population.
The purpose of is to increase public access to high value, machine readable datasets generated by the Executive Branch of the Federal Government.

FedStats: Provides access to the full range of official statistical information produced by the Federal Government with convenient searching and linking capabilities to more than 100 agencies that provide data and trend information.