In response to motorheads request for historic numbers, I am not an expert, but there are few facts i recall from my auto interest reading. Mustang reached 10,000,000 units sold about year two of the S197 (5gen) stang, about 2006. In the same year Corvette hit 1,000,000 units sold. It took vette 41 years that is why I am saying around 2006. There were over 300,000 mustangs sold in 2003 & 2004. A fellow on this web site gave me those numbers, something like 158,000 for 03 and 148,000 for 04. The S197 averaged 160,000 units 2005 and 2006. That 320,000 units in two years (and the Steve McQueen TV ad) is what I believe brought Camaro and Dodge back to the Pony/Muscle car production. In fairness to Camaro their 2009 introduction was into an economy that was collapsed. However, the pent-up demand counted for a lot. In STL, MO there was a $2500 premium on V6 and a $4000 premium on V8 SS and buyers paid it.
I am still surprised Camaro did not show better numbers in June for the motorsport exposure.
I am surprised also by the rise of Challenger. Hey why not? all three of these cars are cool to drive and own. It sets us apart from the 19 out of 20 guys driving front wd v6 minivans and 4 door boring sedans.