In 2008, Jamaal Charles had 67 carries and averaged 5.33 yards per carry. Those 67 carries represent 5% of Charles’ career attempts to date (excluding playoffs). That season, the NFL league average was 4.20 yards per carry, which means Charles was 1.12 (after rounding) YPC above average in 2008, or 1.12 YPC above average on 5% of his career carries.

In ’09, Charles had 190 carries, representing 15% of his career YPC. He averaged 5.89 YPC, and the league average was 4.24, which means Charles was 1.65 YPC above average for 15% of his career carries.

In 2010, those numbers were 230, 18%, 6.38, and 4.21, so Charles was 2.17 YPC above league average on 18% of his career carries.

I performed that analysis for every season of Charles’ career — and every other player in NFL history — to determine each player’s career YPC average relative to league average. The table below shows the 200 running backs (by default, only the top 10 are shown) in pro football history with the most carries. The table is sorted by YPC over league average. Here’s how to read it. Jamaal Charles ranks 1st in YPC over league average. His first year was 2008 and his last year (so far) was 2014. For his career, Charles has 1,249 career rush attempts, which ranks 118th in pro football history. He has 6,856 yards, giving him a 5.49 career YPC average. His “expected” career yards per carry average — based on the league average YPC in each season of his career, weighted by his number of carries — is 4.21. Therefore, Charles has averaged 1.28 YPC above league average for his career, the highest rate in football history.

I’m not a big fan of yards per rush as the primary measure by which we measure running backs, but it’s still interesting to look at the data (for less-popular measures of running back performance that I do find interesting, click here or here). Barry Sanders really stands out in just about every set of analysis one ever does on running backs, but he also is a huge beneficiary of the era adjustment: while he averaged just 0.03 YPC more than Adrian Peterson, the ’90s was a very different era for running backs. After making that adjustment, Sanders has a +0.30 edge on Peterson in YPC over average.

If you sort by the Rush column or the Rk Rsh column, you get a list of the career leaders in attempts. This is another area where Sanders really stands out: Fred Taylor ranks 23rd in career rushes and 23rd in YPC over league average: he’s the only player besides Sanders in the top 25 in both metrics. Several players — Curtis Martin, Jerome Bettis, Edgerrin James, John Riggins, Steven Jackson — rank in the top 20 in rush attempts, are in the Hall of Fame or are borderline HOFers, and yet have a career YPC average below league average (which is one of the reasons why YPC is not one of my favorite statistics).

Here’s another way to look at this data: I plotted each of the 200 players in the graph below. The X-axis displays career carries, from about 800 to 4500; the Y-Axis shows YPC relative to league average, from -0.8 to about 1.5

Pretty interesting: what do you guys think?

Oh, and Billy Ray Barnes? He’s another interesting story. He averaged 3.47 YPC but led the Eagles in rushing yards and rushing touchdowns from ’57 to ’61. But Philadelphia struggled to run the ball during those years, finishing with a 3.54 YPC average, the worst in the NFL. Of course, the Eagles also won the championship in 1960, so these were the glory years for Philadelphia.