The study noted that this year every Mazda model, including the 2016 Mazda 3 and the 2016 MX-5 Miata, met or exceeded fuel economy requirements, a first for any manufacturer that relies on sales of gasoline-powered vehicles.
Previously, only Tesla's all-electric fleet achieved this goal.
This marks the third straight year in which better than half of all passenger car and truck models offered for sale in the U.S. meet or beat national fuel efficiency requirements.
The study looked at fuel economy ratings for 1,094 model-year 2016 vehicles and found that 56.1 percent meet the current CAFE (Corporate Average Fuel Economy) standards established by the U.S. Environmental Protection Agency and the National Highway Traffic Safety Administration.
First established by Congress in 1975, the CAFE standards require automakers' combined passenger vehicle fleets to average 54.5 mpg by 2025.
According to the CFA, the percentage of models with an EPA rating of at least 23 mpg increased from 52 percent in 2016 to 56.1 percent this year, while the number with a rating of 16 mpg or less decreased from 6.1 percent in 2015 to 4 percent in 2016.
"Fuel efficiency increasingly comes standard with new cars, trucks, and SUVs," said Jack Gillis, director of public affairs for CFA, in a statement. "Even if you're in the market for a large pickup or SUV, you'd have to go out of your way to find a true gas guzzler."
The CFA also singled out two other automakers for making significant gains in efficiency: Mitsubishi, which went from 39 percent of models meeting or exceeding standards in 2015 to 70 percent in 2016; and Hyundai, which jumped from 28 percent to 59 percent.
According to the study, of the 16 manufacturers assessed only Ford backslid a bit, going from 34 percent compliance last year to 32 percent in 2016.
However, the CFA did point out that Ford's best-selling vehicle, the 2016 F-150 pickup, showed significant positive fuel economy gains in its class.
In looking at "all-new" models, which the CFA says are the best indication of an automaker's ability to meet CAFE standards, the study found that 63 percent of those introduced in 2016 conformed to regulations, compared to 41 percent in 2015.
Edmunds says: As automakers succeed in meeting or exceeding federal standards, consumers are benefitting from steadily increasing fuel economy.