List of Major League Baseball annual ERA leaders

In baseball, earned run average (ERA) is a statistic used to measure the performance of pitchers. It is determined by dividing the number of earned runs allowed by the number of innings pitched, and multiplying by nine.[a] Major League Baseball recognizes the player in each league[b] with the lowest earned run average each season.[c] The first ERA champion in the National League was George Bradley; in the National League's inaugural 1876 season, Bradley posted a 1.23 ERA for the St.

Source: Wikipedia — List of Major League Baseball annual ERA leaders (CC BY-SA 4.0)