FiveThirtyEight.com published a feature this week about Randall Cunningham's legacy in the NFL, and how it set the stage for an era of dual-threat quarterbacks like Michael Vick, Robert Griffin III, Cam Newton and Russell Wilson.
As good as those players are, FiveThirtyEight's Neil Paine ran some statistical calculations which proved that none of them had a single season better than Cunningham's for the Eagles in 1990.
(Excluding the important statistic of Super Bowl trophies won, that is. But you get the idea.)
Using a statistic called Yards Above Backup Quarterback - think of it as an equivalent to baseball's Wins Above Replacement or Football Outsiders' Yards Above Replacement - Paine reached this conclusion about Cunningham's legacy:
In 1988, he piled up 336 YABQ through the air and 171 on the ground, the first time in league history that combination had ever been achieved.