Per philo:
Dang, the lowest I ever remember gas was 29.9 cents a gallon unless
there was a "gas war" and it would drop a few cents.

Now when it's $2.50 it seems cheap

30 cents in 1965 dollars = $2.50 in 2015 dollars, so it's
really not that much more expensive.... unless somebody has been on a
fixed or some other non-inflation-responsive income.
--
Pete Cresswell