Could all the talk about the upcoming C7 Corvette be affecting prices of the C6 already?

That could be one interpretation of the latest information from cars.com, which is reporting that used late-model Corvettes depreciated the most of any car from July to August 2012.

Corvettes from the 2009 to 2011 model years dipped an average of 6 percent from July 1 to August 1, according to the website.

The average asking price for the Corvette was $55,608 on August 1, down a whopping $3,700 from just a month earlier.

Overall, prices for late-model used cars dropped nearly 1 percent from July to August, or an average of almost $200. However, 2012 continues to show a strong market for used cars, with the average price of $22,177 for 2009-2011 models on Aug. 1 up by $381 over the average on Jan. 1.

The Corvette wasn’t alone in its misery, though. Joining the Chevy with 6 percent price drops were the Ford E250 van, Pontiac G8 sedan, BMW 335i, Porsche Cayenne, and BMW 128i. The Cayenne dipped $3,299 for the month, and the 335i continues to plummet?dropping $2,232 this month after a $3,446 fall the month before.

The news wasn’t bad for all vehicles, however.

The Mercedes S-class and Jeep Grand Cherokee led all vehicles with a 7 percent increase from July to August, followed by a 5 percent increase for the GMC Yukon XL and 4 percent hikes for the Mini Cooper S and Chrysler Town & Country.