The only number I remember specifically was 1970 when the Buick Electra 225 had almost an identical MSRP as a 911 (Targa IIRC). It was the equivalent of $35k in 2015 dollars.
I remember this TV ad as a young kid sitting on the living room floor thinking - Porsche eh...what a weird little car.
Railton
PS. Check out that 60's era Amex card.
How come you never bought a Porsche?
Always put the additional $ some where else. Too practical.
Railton
