Since 2011, total pay for NFL running backs and fullbacks has increased by just 11 percent compared to at least 90 percent for every other offensive position.

Last season, among the N.F.L.’s 32 teams, the 32 highest-paid running backs made an average of $5 million.

In 2013, running backs were typically the sixth-highest-paid position of what could be considered the 11 offensive starters. Now they are the eighth. Last season, on 17 of 32 teams the second-highest-paid wide receiver was paid more than the highest-paid running back.

Since 2000, only 24 percent of starting N.F.L. running backs were still starting four years later, lower than 33 percent for wide receivers and 47 percent for quarterbacks.