Pelton: How I devised the championships added metric

It sounds great on paper: ranking players throughout NBA (and ABA) history based on how they contributed to their team's chances of winning a championship. That's the goal of my championships added metric, which I used to rank the top-40 NBA players of all-time.

So how do we get from the statistics -- in this case, Basketball-Reference.com's win shares, tracked or estimated throughout all of NBA history -- to championships added?

Regular-season championships added