(Grams per mile)

Embedded Dataset Excel:

Dataset Excel:

Notes:

Estimates are by calendar year.  Vehicles types are defined as follows: light-duty vehicles (passenger cars); light-duty trucks (two axle, four tire); heavy-duty vehicles (trucks with more than two axles or four tires); motorcycle (highway only).

Emissions factors are averages based on the national average age distributions, vehicle activity (speeds, operating modes, vehicle-miles traveled fractions, starts and idling), temperatures, inspection/maintenance and antitampering programs, and average gasoline fuel properties in that calendar year. Total HC includes exhaust and evaporative emissions.

Average emissions per vehicle rates assume a fleet comprised exclusively of gasoline and diesel vehicles.  Gasoline-electric hybrids are accounted for in the values for gasoline vehicles.

This table was generated using MOVES4, the U.S. Environmental Protection Agency's (EPA) mobile source emissions model. More information on MOVES is available at www.epa.gov/moves.

Data for this update are based on new estimation models and are not comparable to previous releases. MOVES4 includes updates to historical data and methods as well as updates to future year projections and thus provides the current best estimates of emissions for all calendar years. Data for 2021 and later are projections. 

Description:

KEY: Btu = British thermal unit; CO = carbon monoxide; CO2 = carbon dioxide; HC=hydrocarbons; N = data do not exist; NOx= nitrogen oxides; P = projection; PM2.5 = particulate matter with diameter <=2.5 micrometers; R = revised.

^a Total HC includes exhaust and evaporative emissions.

^b Motorcycle emission rates were last analyzed in 2010.

^c For electric vehicles, total HC and exhaust CO, NOx, PM2.5 and CO2 g/mile values are zero.

Source:

U.S. Environmental Protection Agency, Office of Transportation and Air Quality, personal communication, Jan. 15, 2025.