Typically ~3#'s per inch, however the actual for your particular bow which is highly dependent on the bow design intent, could be quite different.
Shot an osage self bow in March at 3D event.
The bow drew quite smooth to ~27"s and then hit a major wall. I can comfortably draw to anchor, aim, hold, release and follow thru with a bow 10#'s heavier than the specs for this particular bow. My draw is 28" and beyond 27"s for this bow was not going to happen for me. It felt as if I was pulling against a mechanical stop. I tried it numerous times and was just perplexed.
Taking your own measurement will provide the actual.