WASHINGTON—Fuel economy for 2021 model-year passenger vehicles remained the same as 2020 models, which was a record high, while emission levels reached a record low, according to the U.S. Environmental Protection Agency’s (EPA) annual Automotive Trends Report.

Passenger vehicles for the 2021 model year had a fuel economy of 25.4 miles per gallon (mpg). Since model-year 2004, average fuel economy in the U.S. has increased by 32% or 6.1 mpg.

New vehicle real-world carbon dioxide (CO₂) emissions decreased to a record low of 347 grams per mile (g/mi). The average estimated real-world CO₂ emission rate for all new vehicles fell by 2 g/mi to 347 g/mi, the lowest ever reported.

Although all vehicle types are at record low CO₂ emissions, the market shift away from cars toward sport utility vehicles and pickups has offset some of the fleetwide benefits. Since model year 2004, CO₂ emissions have decreased 25%, or 114 g/mi. Over that time, CO₂ emissions have been reduced in 14 of the past 17 years.

According to the EPA, overall advancements in technology are helping the industry reduce carbon emissions.

“Today’s report demonstrates the significant progress we’ve made to ensure clean air for all as automakers continue to innovate and utilize more advanced technologies to cut pollution,” said EPA Administrator Michael S. Regan. “Working together across the public and private sector, we can deliver on EPA’s mission to protect public health, especially our most vulnerable populations, and advance President Biden’s ambitious agenda to combat the climate crisis.”

The EPA found that 2021 model-year cars and station wagons dropped to 26% of new vehicle production. In 2013, the market share for these vehicle types was 50%. SUVs were a record 45% of new vehicle sales, and pickup trucks were 16%.

The EPA found that hybrid vehicles reached a new high of 9% of all production, and the combined category of electric vehicles, plug-in hybrid electric vehicles and fuel-cell vehicles increased to 4% of nationwide production in model year 2021.

Nine vehicle manufacturers exceeded their EPA carbon dioxide emissions standard. They were BMW, Volkswagen, Kia, Nissan, Hyundai, General Motors, Mazda, Stellantis and Mercedes. Five were below their standards, meaning they emitted less than allowed: Tesla, Subaru, Ford, Honda and Toyota.