Patrick Kane had 72 points as a rookie.
His 2nd year Kane had 25 goals and 45 assists for 70 points at 20 years of age.
His third season he had 30 goals and 58 assists for 88 points.
Here's a snippet from an article: RE: Sophmore Slumps
"Many factors come into play when considering the potential for a sophomore slump: The first is shooting percentage. It’s common for players to score goals on a high percentage of their shots as rookies, but suddenly see that rate fall back into the normal range in their second season, leaving fans bewildered as their goal-scoring figures plummet.
Ice time also plays a role in slumping. The more a player plays, the greater the opportunity they have to score and assist goals. If an athlete gets less playing time in their second season, it is difficult for them to maintain or improve production. However, ice time is not the sole measure of opportunity: Audiences must also consider the quality of competition and zone starts. For example, coaches will adjust and try to play to a player’s strengths or push for the development of a more complete game. Matching up with weaker opposing lines and constant starts in the offensive zone can both create misleading stats.
Teammates can play a crucial role too, especially because roster change is inevitable every year. Sometimes, chemistry developed one year can be gone the next. Alternatively, playing with an established star can help boost a player’s production.
Finally, injuries can happen at any point, impeding a player’s progress during the season. The time it takes to get back into shape can also affect the player's performance for the next season. Looking back at past cases, hockey fans can better figure out how much of a role each factor plays.
Since the 2005-06 lockout, 26 rookies have scored at least 0.7 points per game (PPG). Four of those players were from this past season (Laine, Matthews, Marner, and Nylander).
Of the 22 others, nine improved upon their rookie campaign, seven maintained their level of performance, and six meaningfully deteriorated in their second seasons. Those six were Colby Armstrong, Brad Boyes, Ryan Nugent-Hopkins, Marek Svatos, Jeff Skinner, and Nathan MacKinnon.
For Armstrong and Svatos, a decline in shooting percentage was responsible for the drop. The former saw his rate drop by over 10 percent after losing Sidney Crosby as a linemate. Meanwhile, the latter’s astronomically high percentage fell from nearly 20 percent to a more normal 8.4 percent as he scored 17 fewer goals in turn. Among the four breakouts from 2016-2017, however, only Laine and Matthews put forth particularly high shooting rates.
On the other hand, Nugent-Hopkins (shoulder), Skinner (concussion), and MacKinnon (broken foot) were all injured at some point during their sophomore seasons. Each individual’s performance suffered as a result, but once healthy, they returned to their rookie-season forms. Nugent-Hopkins has since turned into a two-way centre and managed 56 points in two consecutive seasons. Skinner, coming off a 37-goal season, looks much more like the prolific goal scorer many predicted after his rookie season. MacKinnon has bounced back with two consecutive 50-point years on a rebuilding Colorado Avalanche team."
Marner had .79 PPG last year.
Marner is at .59 PPG this year.
