I actually looked it up, per EPA in 2022 6343mmt of CO2 were released in U.S - https://www.epa.gov/ghgemissions/inventory-us-greenhouse-gas-emissions-and-sinks

I actually looked it up, per EPA in 2022 6343mmt of CO2 were released in U.S - https://www.epa.gov/ghgemissions/inventory-us-greenhouse-gas-emissions-and-sinks https://www.epa.gov/ghgemissions/inventory-us-greenhouse-gas... So the estimate would range from 0.12% to 0.4% (for 8mmt and 25mmt respectively).