Here's the Value Line "Appreciation Potential" over time:
I've highlighted the range in red over time. Note that it was "wrong" during the 2000 period, but very "right" in 2002-2003. It's currently in harmony with a certain market indicator that I follow.......
in their Selections and Opinions section there's a nice graphic of the Appreciation Potential over the last decade or so. Good correlation to market risk from what I can see. It's a log scale graph, so is a bit hard to read.
Inverting and overlaying makes it a little clearer