Passenger vehicles achieved record-high fuel economy while outperforming greenhouse gas emission standards in model year 2015, according to two reports released this week by the EPA. The GHG Manufacturer Performance Report for 2015 Model Year finds automakers went beyond the model year (MY) 2015 standards by an average 7 grams of CO2 per mile, equivalent to 0.9 miles per gallon (mpg), even as the fleet-wide standard became more stringent by 13 grams of CO2 per mile.