Out of a class of 473 freshman entering the D-1 ranks this year, a grand total of 30 were 18 years of age, representing a mere 6.5% of all incoming freshman. The majority of that 30 were from the NTDP. Only five were Canadian. There were 105 19 year old players entering as freshman, representing 22% of all incoming players. Together as a whole, U-20 players represented less than 30% of all incoming freshman.
The NCAA has been trending older over the past couple of decades. In fact twenty years ago there were over twice as many true freshman (78) and twice as many 19 year old players (209) coming into the league. Five or six years ago the Big 10 floated a proposal to limit the number of 20 and 21 year old freshman but it was overwhelmingly voted down.
Only a handful of schools (the Big 10, a few in the NCHC and a few in Hockey East) will want players to go play in the USHL or Junior A in Canada in order to enter college as true freshman or one year removed. That is not enough programs pushing players into that route to make the USHL still viable against the CHL. The majority of players know they won't be playing college hockey until 20 or 21 years of age; so why not go the CHL?
When this comes to pass, the USHL must work out a deal with the CHL and either become the fourth league under its umbrella or come to some type of affiliation agreement where the USHL will have exclusive rights to players from a certain geographical region (think much of the mid-west and south-western states).
This would be imperative for the USHL because I would think the majority of college programs would want their recruits to take the CHL option not only for the competition but (more importantly) because of the scholarship money given by the CHL to their players to be used for post secondary purposes.