I wouldn't sound the alarms just yet for several reasons.
-It is not apples to apples - The comparison is full player population vs. a single freshman class. Better statistics would be to compare classes at points in time (eg. Class of 2013 as Freshmen vs Class of 2017 as Freshman). Different region's players are more likely to stick around on a lacrosse roster longer.
-The class of 2017 is unique in that there are several new programs outside the traditional LI collegiate interest area. For example Furman has 45 Freshmen on its' roster of 50+. This alone will muddy the statistics. | 
