There’s one simple explanation: There are more opportunities to hit someone now because hitters are extending counts and pitchers are throwing more pitches. The past two full seasons saw the highest number of total pitches (721,282 in 2018 and 721,279 in 2017, according to Baseball-Reference.com) on record.1 But even though the raw counts are higher, the share of total pitches that hit a batter last season is also going up: 0.266 percent of all pitches in 2018 hit a batter, the second-highest share on record. Through Thursday, this season has seen a share of 0.274 percent — which would be the highest that we’ve seen.
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