Does NHL Prospect Improvement Rate Indicate Greater Probability Of Professional Success?

Predicting whether or not a teenager will become an NHL hockey player is not an exact science. There are some critically important intangibles that can be difficult to measure or forecast, typically involving physical growth, work ethic, maturity, development, etc, etc. Are they going to get bigger, stronger, faster, better? How much will they be able to replicate their skill set when they move up to a higher level of competition?

One way talent evaluators like to answer these questions is by looking for "improvements" in its various forms. The theory is that if an amateur player shows improvement year over year he has a better chance of performing at the professional level. To test this theory I looked at a sample of NHL draft picks from 2004 to 2010 who played Canadian junior hockey for at least 2 years after being drafted.

I prefer to measure future value by looking at expected salary and output over the age of 22 to under 26 (I pretend New Year's Eve is on Sept 15). Age 22 is when most prospects finish their Entry Level contract, and Age 26 is most often when players reach unrestricted free agency. Age 23, 24, 25 is the "Draft Analytics Sweet Spot".

The sample of CHL players is then broken off into 2 sub samples; Players who showed at least 10% improvement in points per game both from age 17 to 18 and from 18 to 19. The 2nd sample were Players who had at least a 15% drop in PTS per game either at age 18 or 19. We'll call them the Improvers and Decliners, each group containing over 100 players.

I realize that points alone only measures one aspect of improvement and there are many ways a player can improve that don't show up on a scoresheet (especially with defensemen). However if you are going to do draft analytics, you have a limited number of variables with which to work.

What is the difference between the Improvers and Decliners? One metric to determine value is professional salary. For players on 2 way contracts, this is calculated as their cap hit while in the NHL plus AHL/ECHL (which is just a flat rate of $625 per AHL game and $250 per ECHL game). The results are shown below.

	Decliners	Improvers
Average Entry Level Salary	$145,292	$171,433
Average non-Entry Level Salary	$293,683	$480,710
Avg Career Earnings (age 18-25)	$1,323,739	$1,986,852
Expected NHL GP (18-25)	46	82
% Play at least 100 NHL GP (U26)	12.8%	24.7%
0 Career NHL GP (U26)	65.5%	46.3%
Earning Over $1M Salary (O22-U26)	7.6%	12.5%
Never Play NHL AHL or ECHL (U26)	21.7%	8.9%

The average draft position of Improvers and Decliners is roughly the same, and yet those who show improvement in Canadian junior had statistically significant performance at the professional level than those who declined. These same statistics can be easily calculated for other amateur sources of talent, but the CHL is by far the largest source of future players for the National Hockey League. It has the largest sample size.