Ezra Shaw

This much is indisputable: Three-point shooting has transformed the NBA since it was introduced in the 1979-1980 season. In the first year of its introduction, a mere 5,522 three-pointers were attempted. This year, there were 63,420 three-point field-goal attempts, including 646 by Golden State's Stephen Curry alone. Curry is the league MVP and the three-happy Warriors (Go Oakland!) have been the NBA's best team all season. In the Finals, they've twice started a line-up with no player over 6'7".

Why this change happened is now obvious. If you can make even a modest percentage of shots from three-point range, you will score more points than making even half your two-pointers. So, over time, the NBA teams adapted to this new condition, and began to shoot more and more 3s.


The economist Tyler Cowen, looking at this state of affairs, considers the adoption of three-point shooting as an ominous parable for technological progress. This is, after all, the simplest "technology" out there. All you gotta do is step back a few feet and reap the rewards.

Cowen notes the cultural factors that slowed down the diffusion of the technique.

"Coaches had to figure out three-point strategies, which include rethinking the fast break and different methods of floor spacing and passing; players had to learn those techniques too.  The NBA had to change its rules to encourage more three-pointers (e.g., allowing zone defenses, discouraging isolation plays)," Cowen writes. "General managers had to realize that Rick Pitino, though perhaps a bad NBA coach, was not a total fool, and that the Phoenix Suns were not a fluke.  People had to ponder the expected value concept a little more carefully.  Line-ups had to be smaller.  And so on.  Most of all, coaches and general managers needed the vision to see how all these pieces could fit together."


Add all those factors up, he says, and it's taken 35 years for teams to catch on to the importance of the 3 ball. This becomes an allegory for his argument about The Great Stagnation. This is Cowen's idea, distributed in a short e-book of that name in 2011, that perhaps the world has used all the easy economic-growth-promoting ideas in science and engineering—so now we're stuck.

"So how long do ordinary scientific inventions need to serve up their fruits?" Cowen concludes his three-pointer post. "I am a big fan of Stephen Curry, but in fact his family tale is ultimately a sobering one."

It's an interesting argument, but this chart doesn't look like lack of progress to me.

Data in chart adjusted for strike-shortened seasons in 1999 and 2011.
Alexis Madrigal

NBA teams have shot 1600 more 3-pointers per season since 1980. That works out to a compound annual growth rate of about 7 percent. So, while it is certainly true that it has taken time for the glory of the Stephen Curry era to emerge, it's also true that the diffusion of the tactic has been strong and steady for 36 years.

Cowen's point still holds: this is evolutionary, not revolutionary progress. And teams in 1986 probably should have simply taken 5 times as many three-pointers than they did.

But there's another technological lesson I draw from the three-pointer-parable: so many technologies seem to arrive all of a sudden—when an iPhone or a Warriors offense arrive on the scene—but their actual adoption has taken much longer than you'd think.