a few things make this hard to predict
one old metric used to be that you could double your money every 7 years
in the case of the dow and s & p, it's just getting back to where it was, after being cut in half 7 years ago, following a bubble
also, the dollar has been roughly cut in half in the last 7 years, so adjusted for inflation, dow ir s & p at these levels buys less than it did 7 years ago, so it's true 'value' is still much less
as a crosscurrent, we have had a steepening near parabolic rise without any pullback
so it's really uncharted territory, anything can happen.