It is not necessary to shout to get your point across.
Here is a link to an article written by Dr. Chris Rosenberry in which he explains how the game commission arrives at the estimated numbers.
http://www.pgc.state.pa.us/pgc/cwp/view.asp?a=465&q=151378
While the article is long, if you manage to read it through to the end I think you will have a fairly good idea how the numbers are determined. There is never going to be any way that an estimate would be as good as an actual counted number, but for the present, it is probably the best they can possibly do, until such time as all sportsmen who harvest a deer send in their report cards, that is.