I like to use this stat (Runs Created per 27 outs) when searching for players. It is a "rate" stat, for those who are not familar with it. It is used to approximate the expected number of runs your offense would score in a game if you batted nothing but that player's season over and over again.

Anyway, I was looking at Bert Campaneris earlier. His last two seasons are '81 and '83. Here are his AVG/OBP/SLUG for those two seasons, as well as his RC27 as listed by WIS:

'81: .256/.295/.341 for RC27 of 3.63
'83: .322/.355/.357 for RC27 of 3.96

It seemed to me that the 1983 number was not high enough, at least compared to 1981. So I googled the formula and calculated it for both seasons; I got about the same number that WIS did for 1981, but got 4.61 for 1983. Which is a pretty big difference.

Anybody else notice that RC27 is off? Is this a systemic bug or just a scrivner's error or something?

RC	Runs Created (((Hits + BB + HBP - CS - GIDP) * (TB + .26 * (BB - IBB + HBP) + .52 * (SH + SF + SB))) / (AB + BB + HBP + SH+ SF))
RC27	Runs Created per 27 Outs (RC / ((AB - Hits + CS) / 25.5))

I'm sure you're aware of these but here are the 2 formulas in calculating the stats, I didn't do the math but I can't see it being to far off. From my experience it is not a good "stat predictor" as far as in season production, so I went away from it. It really favors power hitters and somewhat high SB% guys. I do use the RC stat in the performance history quite a bit as a tool if I'm having difficulty choosing between a couple players but even there some players numbers are off due to small sample size.

www.baseball-reference.com has 3.6 for 1981 and 3.8 for 1983.

They may be using slightly different versions of the formulas than WIS, but the numbers look right to me.

When I calculate it using the versions of the formulas posted by duece, I get 3.63 for 1981 and 3.96 for 1983, the exact same numbers as WIS is using.

I don't see any error here.