This is true; regarding this specific time period, however, there were definitely some large historical events that contributed to prices rising. The logarithm

This is true; regarding this specific time period, however, there were definitely some large historical events that contributed to prices rising. The logarithmic scale reveals it as well. Vietnam, yes, but also that whole patriotism thing, news reporting, and "Buy American" which was, obviously, fueled by the birth of the advertising age.