Max flaccid length to (reasonably) expect as a % of erect?

First, 2 preliminary questions: when measuring flaccid length, is it common to use BP or NBP? And how much does BP usually add to the overall length? (I’m fairly lean, and bone pressing gives me about a another 1/2” which, based on Search, seems to be about typical for everyone else)

Main question: What’s the max flaccid length to (reasonably) expect as a percentage of erect?

For instance, if I’m 7” NBPEL and my flaccid is about 5.5” NBP (or would you guys use BP for this?) that’s almost 80% Is that about as long as my flaccid will probably get compared to my erect size? Or can I get it to 6” or 6.5”? (about 90%) or maybe very nearly 7” (~100%) the same as my erect length?

OK, I’ll make this much simpler…

If a guy is 7” x 5” erect, can he also be about 7” x 5” flaccid with proper PE exercises?

No. While I have not seen every dick in the world throughout history, I wager to say that all flaccids shrink back to some degree.

Now, if you’re talking about a flaccid that you manually stretch out, that’s a different story.