Baseball Statistics & Tips : How to Calculate an Earned Run Average
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One year Ron had the lowest ERA (earned-run average, mean number of runs yielded
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The true barometer is the earned run average
In baseball statistics, earned run average (ERA) is the mean of earned runs given up by a pitcher per nine innings pitched. It is determined by dividing the number of earned runs allowed by the number of innings pitched and multiplying by nine. Runs resulting from defensive errors are recorded as unearned runs and omitted from ERA calculations.