At some point several months ago, I got into a discussion with somebody on hfboards about the number of CHL players drafted into the NHL. If I find the original thread again, I'll update this post with a link. I thought I'd saved the link, but I guess not.
Methodology, assumptions, and conclusion in the extended entry.
I posted this on hfboards here.

We'll set the bar at a minimum of 150 games played to be considered to have "made it". That gives us two seasons and a few cups of coffee. Obviously this eliminates anybody drafted 2003-2005, but I'll include their numbers for interest sake. Since I glommed the data from hockeydb's draft pages, this season's figures are *not* included.
I have *not* corrected for players drafted twice; for instance, Jarret Stoll will be counted twice as a WHL draftee, and Matthew Lombardi twice as a QMJHL draftee. I can correct for this, but won't just yet. Percentages are rounded off so they won't quite add up.
First, raw numbers. In the ten year span of draft classes, we see 2936 players drafted in total. Since we're not (currently) interested in non-CHL players, the breakdown is as such:
League | Drafted | Percentage | Made it
WHL | 515 | 17.5 | 43
OHL | 503 | 17.1 | 33
QMJHL | 304 | 10.4 | 28
(CHL | 1322 | 45.0 | 104)
Others | 1614 | 55.0 | 95
Eliminating the 2003-2005 draft classes, we cull out 812 players, leaving 2124. So, here we go again, this time with the 1995 - 2002 draft classes.
League | Drafted | Made it | Percentage
WHL | 387 | 43 | 11.1
OHL | 375 | 33 | 8.8
QMJHL | 216 | 28 | 12.9
(CHL | 978 | 104 | 10.6)
Others | 1146 | 95 | 8.2
See, we eliminated nobody (made it column), not really a surprise. So I calculated the "percent that made it" here.
104 of 1322 CHL players drafted in the last 10 years can be considered to have "made it" if you set the bar at 150 games. Remove the players that couldn't possibly yet have made it, and the number is 104 of 978. So, successful CHL players make up approximately 4.8% of all players drafted to the NHL from 1995-2002 inclusive.
As stated, I glommed the draft records from With some persuading, I could probably make the raw data I used available as a CSV text file, but I'd want to clear the re-distribution with the owner of hockeydb first.