Colorado officials say greenhouse gas emissions in the state peaked in 2010 and have been in decline since.
Colorado Air Pollution Control Division Director Gary Kaufman says the decline rate has been small, but it is expected to increase by 2030.
The data is included in the Colorado Public Health and Environment's draft inventory of the state's greenhouse gases.
The report projects 125.5 million metric tons of carbon dioxide, methane, nitrous oxide and other gases will be emitted in the state in 2020. That's down from nearly 127 million metric tons in 2015 and 133 million metric tons in 2010.
A new state law aims to cut emissions to at least 90% of 2005 levels, or about 113 million metric tons, by 2050. Officials project the state will still be well above that goal in 2030.