This week, Advanced Stat of the Week will look at running back success rate. Success rate is one of the most important ways to judge the true effectiveness of a runner. Consider the following hypothetical runners.
Runner A has one 80-yard carry and nine carries for no gain. His stats are 80 yards, 10.0 yards per carry.
Runner B has eight 10-yard carries. Two of his carries came on 3rd-and-15. His stats are 80 yards, 10.0 yards per carry.
Runner C has 20 carries, for four yards each, but all his carries came on 3rd-and-3 or less. His stats are 80 yards, 4.0 yards per carry.
The back who helped his team win was the back with the fewest yards per carry, but the most successful runs.
Success rate illustrates that a runner's ability to move the chains is his most important quality. "Boom and bust" backs can be exciting, but carries for negative yards are drive killers. Long runs thrill fans, but consistent gains are more valuable.
The FootballOutsiders calculate success rate roughly in terms of the percentage of yards gained by the runner each down. On first down, a back needs 40 percent of the yards his team needs for a first down. On second down, that jumps to 50 percent. On third and fourth down, a run is only successful if the back gets 100 percent of the necessary yards.
In terms of success rate, a three-yard run on 1st-and-10 is not successful. A three-yard run on 2nd-and-5 is successful. An eight-yard run on 3rd-and-10 is not successful. This sliding scale helps account for meaningless yards that a back accrues during the course of the game. Seven-yard gains on a draw on 4th-and-20 don't often mean much in the course of a football game, and Success Rate shows us that. A running back should be looking for a success rate north of 50 percent.
Maurice Jones-Drew of the Jaguars is the most underrated player in the NFL. It's nice that he won the rushing title in 2011, but he hardly needed it to validate his career. He's been brilliant from day one of his tenure with the Jaguars, and the accolades that came his way in 2011 were certainly hard earned.
One of the most impressive things about Jones-Drew is his consistency. Success rate helps illustrate just how steady the running back has been. Despite having the ability to break big plays, Jones-Drew has been remarkably good on the short carries as well. The AFC South has some tremendous running backs, but if anyone is looking for a reason to support Jones-Drew as the best of the bunch, success rate is a handy tiebreaker. His utility over someone like Chris Johnson cannot be questioned.
His ability to move the chains and pick up the hard yards is what separates Jones-Drew from other running backs. While I have concerns about his durability going forward, there's little question that he's been one of the dominant players in the AFC for the past several years.