Well, this whole exercise is bunk since the 4.88 is his 2016 number. His 2015 number was 3.98.
But anyhow, I'm not so sure of your math.
Freddy's total pay in 2014 was 3,850.
McCoy's in 2015 was 5,500.
Freddy had 1,026 in 2015.
In 2016 McCoy had 1,187.
That's $3,752.43/yard vs. $4,633.52.
Shady was 1.23 times more expensive than Fred on a per yard basis. Not "three times."
Your math counts his half game against WAS as a full game to get to your YPG number. And you've completely omitted his receiving production in those games. Why'd you do that?