Originally Posted by RedsBaron
While Wilson's ERA has dropped each of the last four years, so has the NL's ERA. BaseballReference.Com includes ERAs adjusted for playing conditions. In each of the last four seasons, Wilson's ERA was higher than the adjusted NL average: 4.88 to 4.48, 4.83 to 4.47, 4.64 to 4.29 and 4.36 to 4.01.
BaseballReference.Com also has an adjusted ERA for pitchers, where the higher the score the better, as it measures a pitcher against the league norm. For example, in 2004 Randy Johnson had an ERA of 2.60-matched against a league norm of 100, Johnson's score was 171. Wilson has been remarkably consistent by that measure-each of the last four seasons he has had a score of 92 versus a league average of 100. I'm sure WOY or Steel could explain this better, but as I understand it, this means that in all four seasons Wilson was mediocre, just below the average.