We all know that Damian Lillard is good. I mean, REALLY good.
Talk about an outlier.
TPA (total points added) is defined as:
The formula for TPA is rather simple. It’s broken down into two parts—offensive points added (OPA) and defensive points saved (DPS)—and each is calculated in the same vein.
OPA is derived by adjusting offensive box plus/minus (OBPM) to account for the number of possessions the player in question is present for. Similarly, DPS is derived from a similar adjustment of defensive box plus/minus (DBPM) with that same number of possessions. OBPM and DBPM, both calculated by Basketball-Reference.com, estimate the per-100-possessions value of a player on either end of the court.
Add OPA and DPS together, and you have TPA. A score of zero indicates a player was perfectly average (by no means a bad thing for rookies or lifelong end-of-bench players), while anything positive means they were better than an average-level replacement.