I lived through the 1970s, and am MUCH less concerned about inflation than the impact of deflation. At least with inflation---unless it reaches Weimar Germany proportions---there is a psychology of "good times," but with deflation, studies have shown that even when people actually may be doing better, the perception of falling wages is depressing and has all sorts of spinoff effects.
Do not forget to add to this that the factor changes as well. 50 years ago a $1 move in any DOW stock equated to a $1 move in the Dow. Over time that factor has changed so that a .25 move in any Dow stock produces a $1 move in the Dow. If the factor never changed the Dow would be between 1,100 and 1,300