The Statistical Abstract of the United States, published since 1878, is the authoritative and comprehensive summary of statistics on the social, political, and economic organization of the United States.
Drill down by issue/topic to find which government agency/department might have statistics. Or use the search box at the top. It works like other search engines, but only returns results from government web pages.
This site has not been updated since 2015, but it has a good list of resources - you may need to use a search engine (like Google) if a link is broken to find the updated website address.
The Human Development Index (HDI) is a composite index of life expectancy, education, and per capita income indicators, which are used to rank countries into four tiers of human development.
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