Bureau of Justice Statistics http://www.bjs.gov/
Statistical information on crime, criminal offenders, victims of crime, and the operation of justice systems at all levels of government
National Center for Education Statistics http://nces.ed.gov/
Data for public schools, public school systems; limited data on private schools by state, county, individual school or school district.
Energy Information Administration http://www.eia.gov/reports/
Data, reports, forecasts, analytical content, and documentation; as tools for user-customized data queries.
Healthcare Costs and Insurance
U.S. Census Bureau http://www.census.gov/hhes/www/hlthins/index.html
From Current Population Surveys, American Community Survey, and Survey of Income and Program Participation
Agency for Healthcare Cost and Utilization [DHHS] http://www.ahrq.gov/research/data/index.html
Homeland Security https://www.dhs.gov/immigration-statistics
Core reports on immigrants by legal status. Also quantitative studies and research on immigration.
Poverty, Income, Health Insurance
U.S. Census Bureau http://www.census.gov/topics/income-poverty/poverty.html
Public Welfare Programs
Social Security Research, Statistics, and Policy https://www.ssa.gov/policy/
TANF (Temporary Assistance for Needy Families) Office of Family Assistance
Bureau of Labor Statistics http://www.bls.gov/bls/unemployment.htm
Free online access to official publications from all three branches of the Federal Government.
Open source data from U.S. Government sources
Statistics from over 100 federal agencies
United States Census Bureau http://www.census.gov/en.html
The Leading source of high-quality data about the Nation's people and economy
Statistical Abstract of the United States
The authoritative and comprehensive summary of statistics on the social, political, and economic organization of the United States. Library also has 1937-present at C 3.134 in Government Documents