Light-duty 2013 model-year vehicles reached an all-time high in fuel economy with an average of 24.1 mpg as a result of technologies such as gasoline direct injection engines, turbochargers, and advanced transmissions, according to the Environmental Protection Agency.

The EPA's annual study of light-duty fuel economy also named Mazda as the OEM with the highest average fuel economy and greatest improvement in greenhouse gas emissions. Additionally, Nissan achieved the greatest improvement in average fuel economy. Among vehicle classes, SUVs achieved the greatest improvement.

Nissan logged a 26.2 mpg for its 2013-MY vehicle lineup, achieving a 2.1 mpg improvement from its 2012-MY vehicles.

Fuel economy has increased in eight of the past nine years, and increased nearly 5 mpg since 2004. The average carbon dioxide emissions reached a record low of 369 grams per mile, according to the report.

Read the full report here.