Draft Metrics: Running Backs

It's important to know what kind of production to expect from your running back, and targeting the right round to meet that expectation should increase the success of meeting needs with draft picks. I've charted rush yards per year and combined yards per year vs round drafted for running backs drafted since 2002 (to focus on current backs, given the expected career for them is about 8 years). A very interesting trend develops: if we remove the two 1st-round outliers (Chris Johnson, Adrian Peterson), there is virtually no difference in the peak performance per round on day 1. As expected, the average performance decreases with round.

First, let's take a look at the Rush Yards per Year and Combined Yards per Year vs Draft Round graphs (see full data here):

We see very similar distributions in both, suggesting there's no significant change in usage for backs taken in early rounds vs later ones. We also see a gradual dropoff in average career production with round, and no 1st rounder has failed to play at least one year (though this is not surprising given the money invested in them, and I expect this theme to persist for other positions).
So then, where should your team look for a back? As mentioned before, there are 2 exceptional backs from the last 8 years, and neither is the type of talent that is available in any draft. There is approximately 1 back per draft that will average over 1000 yards per year, 3 of whom came from the 1st round, 2 from the 2nd, and 1 each from the 3rd and 4th. Hence, the top back per draft can be lurking anywhere on day 1.

Digging deeper into the talent pool, we come up with 20 backs who averaged at least 800 yards per season (1st: 11, 2nd: 5, 3rd: 3, 4th: 1), which is about what we'd expect from a quality feature back. More than half of them are found in the first round, and an overwhelming majority come from the first two rounds.

Rounds 3 and 4 produce many solid backups, or players for multiple-back systems, but virtually no stars. Players from this range may have a few good years, but don't sustain success (Brandon Jacobs, Jerious Norwood). Careers average about 5 years.

Rounds 5 and later rarely produce anyone better than backup quality, Michael Turner and Tim Hightower being the exceptions. About a third of these players will never make an NFL roster.