<Table> <Tr> <Td> </Td> <Td> This section does not cite any sources . Please help improve this section by adding citations to reliable sources . Unsourced material may be challenged and removed . (April 2017) (Learn how and when to remove this template message) </Td> </Tr> </Table> <Tr> <Td> </Td> <Td> This section does not cite any sources . Please help improve this section by adding citations to reliable sources . Unsourced material may be challenged and removed . (April 2017) (Learn how and when to remove this template message) </Td> </Tr> <P> As with batting average, the definition of a "good" ERA varies from year to year . During the dead - ball era of the 1900s and 1910s, an ERA below 2.00 (two earned runs allowed per nine innings) was considered good . In the late 1920s and through the 1930s, when conditions of the game changed in a way that strongly favored hitters, a good ERA was below 4.00; only the highest caliber pitchers, for example Dazzy Vance or Lefty Grove, would consistently post an ERA under 3.00 during these years . In the 1960s, sub-2.00 ERAs returned, as other influences such as ballparks with different dimensions were introduced . Today, an ERA under 4.00 is again considered good . </P> <P> The all - time single - season record for the lowest ERA, according to www.mlb.com, the official website of Major League Baseball, is held by Dutch Leonard, who in 1914 had an earned run average of 0.96, pitching 224.2 innings with a win - loss record of 19 - 5 . The all - time record for the lowest single season earned run average by a pitcher pitching 300 or more innings is 1.12, set by Bob Gibson in 1968 . The record for the lowest career earned run average is 1.82, held by Ed Walsh, who played from 1904 through 1917 . </P>

Is it better to have a lower or higher era