I don't think it is possible to determine a read close figure for the number still on the road. That said, some educated guesses can be made. First, back in the 70's cars didn't last all that long, say, maybe 10 years or less. Second, you would need to allow for the fact that folks that had Vettes probably kept them longer say another 5 years. And, then, they passed to people willing to work to keep them on the road, maybe add another 5 years. However, and third, Vettes suffer badly in accidents and are expensive to fix so they meet an early end. Add that to the fact that Vette drivers usually are not little old ladies and many push the pedal leading to accidents. So take maybe take 8 years off the longevity. Time takes its toll and frames rust, fiberglass cracks, engines die and when they sit outside unused for years they deteriorate. Take another 5 years off. Fourth, lots of people love Vettes and they try to keep and preserve them, add 5 years. You can do the actual math extimates. Within 10 miles of my house I know of 6 that are just about beyond saving without spending many thousands. They won't see the road again. Plus, I know of 5 more within 40 miles that are pretty much dead. I would guess that of the 305,000 you mentioned less than 10,000 survive.
