High Quality Content by WIKIPEDIA articles! Adjusted ERA+, often simply abbreviated to ERA+ or ERA plus, is a pitching statistic in baseball. It adjusts a pitcher`s earned run average (ERA) according to the pitcher`s ballpark (in case the ballpark favors batters or pitchers) and the ERA of the pitcher`s league. Average ERA+ is set to be 100; a score above 100 indicates that the pitcher performed better than average, below 100 indicates worse than average.