EPA released its 30th annual Inventory of U.S. Greenhouse Gas Emissions and Sinks (GHG Inventory), which presents a national-level overview of annual greenhouse gas emissions from 1990 to 2021. Net U.S. greenhouse gas emissions were 5,586 million metric tons of carbon dioxide equivalent in 2021, a 6% increase in emissions from 2020. The increase is largely due to a rebound in economic activity following the height of the coronavirus (COVID-19) pandemic. However, emissions have declined overall since 2005 (17%), which reflects the combined impacts of several factors, including energy market trends, technological changes including energy efficiency improvements, and the carbon intensity of energy fuel choices. For this latest release, EPA has made several important improvements, including updates to estimates for oil and gas and for flooded lands such as hydroelectric and agricultural reservoirs.