Home Runs Were Down in April, but by How Much?
Seemingly in the blink of an eye, a month of baseball is behind us. With nearly 30,000 plate appearances taken and more than 18,000 batted balls put into play, a month of data is plenty to begin examining league-wide trends and to make some predictions for the rest of 2021.
One big question going into this season — and a topic already examined here by both Ben Clemens and Justin Choi — was what the impact of the new baseball would be on the overall offensive environment. As both Ben and Justin found and detailed, the new baseball is bouncier, yielding higher exit velocities than in years past, and also possesses more drag, as it is not traveling as far. I want to focus on that second point. If the ball isn’t traveling as far, we should be seeing fewer home runs hit in 2021 — and we are. But can we pinpoint just how many home runs will be hit this season? That takes a bit more guesswork, but before getting into that, let’s first see how April 2021 stacks up to prior seasons, as well as identify where exactly we lost those home runs.
Year | HR | BBE | HR/BBE% |
---|---|---|---|
2015 | 592 | 17559 | 3.37% |
2016 | 740 | 18498 | 4.00% |
2017 | 863 | 19301 | 4.47% |
2018 | 912 | 21706 | 4.20% |
2019 | 1144 | 22111 | 5.17% |
2021 | 873 | 18509 | 4.72% |