In real (constant dollar) terms, today's national average is 16% BELOW the 1939 price in your photograph!
My figures for today’s inflated FRAUD (Federal Reserve Accounting Unit Denominator erroneously called “dollars”) also came from an official and assumed to be accurate source.
The bottom line is that since the creation of the Fed in 1913 and the removal of precious metal backing of the currency in 1965, we’re been screwed, blued and tatooed.