Used vehicles fell 12.1 percent in value during 2014, which represented a slight improvement from 2013, which saw a 12.8 percent depreciation, according to Black Book.

The year finished strong for residual values, as vehicles from model years 2009-2013 sold at auction fell 1 percent in value in December after a 1.9-percent decline in November. Average annual pre-recession depreciation falls between minus 15 to minus 18 percent.

Full-size passenger vans led all categories during the year, and increased 3.5 percent in value, while prestige luxury cars fell hardest with an 18.1 percent decline. With falling gasoline prices, trucks, SUVs and full-size vans had the strongest showing during the year of the 24 categories. Domestic trucks fell 9.1 percent to $18,970 on the year, while domestic cars fell 15.9 percent to $11,976.

Full-size cargo vans depreciated only 3.8 percent. Other strong categories include compact pickups (down 4.3 percent to $15,610), compact SUVs (down 5.2 percent $19,358), full-size pickups (down 6.6 percent to $25,612), and mid-size pickups (down 7 percent to $16,707).

Car categories fared worse. Mid-size sedans found in fleets fell 14.8 percent to $11,273 when included with entry mid-size cars and 15.4 percent to $11,078 when included with upper mid-size cars. The Chevrolet Malibu is considered an entry mid-size car, while the Mazda6, Subaru Legacy, and Volkswagen Passat would be upper mid-size cars.

For December, full-size cargo vans and passenger vans finished tied with the strongest retention by increasing 0.5 percent in value. Compact SUVs also finished the month in positive territory by increasing 0.2 percent. Entry-level cars recorded the lowest monthly depreciation among cars by finishing mostly unchanged at minus 0.2 percent.