Backstrom is good but this is nearly meaningless when half his assists are from the power play where ovechkin is one of the best power play shooters of all time.
86 of his 520 career assists come from goals scored by Alex Ovechkin on the powerplay.
That is 16.5% of his total assists.
If one subtracts all of Ovechkin's powerplay goals from the equation, Backstrom still would have 434 assists in 708 games, or 0.613 assists per game. That would slot him comfortably in 8th place on that list, just underneath Patrick Kane.
Backstrom assists on an Ovechkin powerplay goal at a rate of once every 8.23 games, or approximately 10 times per season. Of course, it takes some work on the part of Backstrom as well to create the opportunities for Ovechkin to score in those situations.
If we halved the number of Ovechkin powerplay goals that he assisted on -- let's say, for example, throughout his career he only assisted on 43 of Ovechkin's powerplay goals, or played with someone half as proficient as Ovechkin is on the powerplay -- he would be in 5th place on the list, just beneath Jaromir Jagr, with an average of 0.673 assists per game.
Right now, Nicklas Backstrom is tied for second in NHL scoring with 60 points in 56 games; he is one point behind Connor McDavid. So far in 2016-17, he has assisted on only 13 of Alex Ovechkin's goals. He currently has 43 total assists, tied with McDavid for the league lead.
This season, Backstrom has scored at a rate of 2.54 assists per 60 minutes. McDavid has scored at a rate of 2.17 assists per 60 minutes.
Sidney Crosby, meanwhile, has only scored at a rate of 1.92 assists per 60 minutes this season; Evgeni Malkin: 2.21 assists per 60 minutes.