Speed score (Spd) is a statistic developed by Bill James that rates a player on their speed and baserunning ability. Different locations include slightly different components, but the FanGraphs version consists of, “…Stolen Base Percentage, Frequency of Stolen Base Attempts, Percentage of Triples, and Runs Scored Percentage.”
Speed score is a bit of an outdated stat at this point, as it doesn’t account for all aspects of baserunning and its results aren’t presented on a “runs above average” scale. Instead, if you’re looking for a measure of how much value a player adds to their team through their baserunning, check out the statistic Ultimate Base Running (UBR).
Please note that the following chart is meant as an estimate, and that league-average Speed Score varies on a year-by-year basis. To see the league-average Spd for every year from 1901 to the present, check the FanGraphs leaderboards.
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