University of Pennsylvania - Historical Statistics - Research Guide
The best online source for historical statistics. Searching for U. S. historical statistics? This is the place to start. Reaching back into the past as far as records have been kept, this site has links that connect to a wide variety of databases. It also includes bibliographic records of print sources. It covers national and international historical statistics.
This website covers everything from housing and immigration to religion and agriculture. The Guide to History Databases on the left side of the home page has links to separate pages providing guidelines for in-depth research. Although some of the links are password protected, many are open and accessible to the public.