In baseball, an earned run is any run that was not necessarily enabled by a fielding error or a passed ball. In other words, an unearned run is one run that would not have been scored without the aid of an error or a passed ball committed by the defense, and an earned run is simply one that is not unearned. An error made by the pitcher in fielding at his position is counted the same as an error by any other player.Regardless of the name, an unearned run is credited to the offensive team's score the same as any other run. It is only "unearned" in that it was, in a sense, "given away" by the defensive team.Both total runs and earned runs are tabulated as part of a pitcher's statistics, but earned runs are specially denoted because of their use in calculating a pitcher's earned run average (ERA). One of the most prominent of baseball's traditional statistics for pitchers, the ERA is defined as the number of earned runs allowed per 9 innings pitched (i.e., averaged over a regulation game). Thus, in effect, the pitcher is held especially accountable for earned runs, while the responsibility for unearned runs is shared with the rest of the team.To determine whether a run is earned, the official scorer must reconstruct the inning as it would have occurred without the errors (for purposes of this rule, the "errors" also include passed balls). The benefit of the doubt is always given to the pitcher in determining which bases would have been reached by errorless play.If no errors and no passed balls occur during the inning, all runs scored are automatically earned (assigned responsible to the pitcher). In a few cases, an error can be rendered harmless as the inning progresses. For example, a runner on first base advances to second on a passed ball and the next batter walks. Since the runner would now have been at second anyway, the passed ball no longer has any effect on the earned/unearned calculation. On the other hand, a batter/runner may make his entire circuit around the bases without the aid of an error, yet the run would be counted as unearned if an error prevented the third out from being made before he came up to bat.