Pew Research reported anywhere from 35-48% (lower number with identifying, upper number with "leaners") of Americans identifying as Democrats in 2012 (the year of that article). It isn't a leap to assume that 18% that consider Bill Clinton "Outstanding" comes entirely from the Democrat side. With the lower number of Democrats, over half would have an "Outstanding" view of him, or did 4 years ago anyway. Total approval numbers have increased since then, and it would be somewhat odd if total approval went up but no increase in "Outstanding" evaluations. By the nature of older data there's a little but of conjecture about the exact current status, but you can't suggest my statements are baseless. You also are too knowledgeable on this sort of subject for me to need to lay all that out.