The NBA introduced the three-point field goal for the 1979-80 season. That year, the average NBA team attempted 2.8 three-point shots per game, make less than one per game (0.8).

Over the course of the next four seasons, teams averaged only 0.5–0.6 three-pointers per game. So the average NBA game in the early 80's saw only one made three-pointer on average. During that period, teams averaged 108–110 points per game.

Starting in the 1984-85 season, use of the three-pointer began to rise. Over the course of the next 25 seasons, we see a steady rise in both three-pointers attempted and three-pointers made. In fact the rise is nearly linear. If we ignore the three year period (1994-95 through 1996-97) in which the NBA shortened the distance to the three-point line*, the R-squared value for both lines is .98 during that 25-year period.

Interestingly, scoring in the NBA has fallen during the period when three-pointers were on the rise. Scoring peaked in 1984-85 at 110.8 points per team per game. That number fell all the way to 91.6 during the 1998-99 season before experiencing a small rebound in the last 10 years.

We also see that use of the three-pointer may finally be leveling off. After seeing a steady rise for 25 years, there has been little change over the last four seasons. During that period, teams averaged 17.4–18.1 three-point shots per game and 6.4–6.7 three-pointers made.

Moving forward, it will be interesting to see if the NBA is content with where these numbers are, or if they will tinker with the rules to try and bring scoring back to the levels seen in the mid-80s.

*The NBA 3-point line is 23'9" at the top of the key and 22'0" in the corners. From 1994-95 through 1996-97, the NBA made the 3-point line a uniform 22'0".

All data via Basketball-Reference.com