By most measures, production of uranium concentrate (U3O8) remained at or near all-time lows in the United States during 2021, at 21,000 pounds, which is less than 1% of the post-2000 production high of 4.9 million pounds U3O8 in 2014. As domestic production has declined, an increasing amount of the uranium purchased for use in U.S. commercial nuclear power reactors has been from other countries.