Walks plus Hits per Innings Pitched (WHIP) measures how many base runners a pitcher lets up. It’s formula is exactly as it sounds: walks plus hits, all divided by innings pitched. It’s a common statistic in fantasy baseball leagues, but it’s a poor evaluative tool since pitchers have little control over their Batting Average on Balls in Play (BABIP) rate.
If you want to get serious about evaluating a pitcher’s ability level at preventing baserunners, look instead at their walk rate, BABIP, and batted ball profile. Pitchers do control their walk rates, but their hit rates reside largely outside their control and are prone to fluctuations.
Great pitchers will typically have lower WHIPs, and questionable pitchers will have higher WHIPs. However, since hit rates vary depending upon a pitcher’s BABIP, WHIP values are also prone to fluctuating.
Please note that the following chart is meant as an estimate, and that league-average WHIP varies on a year-by-year basis. To see the league-average WHIP for every year from 1901 to the present, check the FanGraphs leaderboards.
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