But what about the range of peak when we lower our sample size? Years ago here we created an MVP calculation tool using two-month snapshots, and it produced interesting but inconsistent results (thus not proving worthy of automation). Two-month snapshots gave us peaks and valleys that had a 20-25% greater range from top to bottom, which meant that they were not particularly well-correlated to a full season's worth of data.
So in looking for a more congenial relationship between seasonal performance range and a sub-set of seasonal data that occupies that range, we move onto three-month snapshots (we'll call them "slices," since that's what we called 'em in the title). Rather than dive right into rate stats, however, we're going to spend some time with counting stats, as they will give us some interesting benchmarks with respect to peak performance.
We start with homers, because--well, why not? We can concoct some pleasurable trivia in determining who hit the most homers over a three-month period. Note, however, that for this exercise we are restricting ourselves to actual months, and not all possible 30-31 game units that could be measured via David Pinto's Day-by-Day Database (found at his Baseball Musings site. You'll have to wait for us to get around to knowing who hit the most homers, etc., from June 8-July 7, 2019 (or, in terms of our "three-month slices," June 8-September 7: aw, what the hell: the answer is Mike Trout, with 29).
As the table you're seeing at the right indicates, however, Trout's total isn't enough to get him on the all-time leaders list for most HRs in a three-month slice. That record--42--was set (appropriately enough) in 1998, when Mark McGwire moved to St. Louis from Oakland in September of the previous years and started hitting HRs at a record pace. Sammy Sosa matched him later in that year; McGwire did it again in 1999.
So--the HR record for a season is 73 (those screaming "cheater!" are excused...) and the record for a (rough) half-season is 42. That presupposes a 15% "drag" between the extrapolated full-season total if the pace in the three-month slice could be maintained (73/(2*42 or 84).
There are 49 three-month slices listed in the table as it descends from 42 to 32. As we peruse the names (there are a few surprises: Christian Yelich, Jay Buhner, Greg Vaughn, Luis Gonzalez) we can also create a log of who held the record for this odd little stat.
It's not particularly surprising to discover that Babe Ruth set the record within the first four months of the live ball in 1920: his 37 HRs in May, June, and July 1920 was tied (Ruth again in May-July 1928, and Jimmie Foxx in May-July 1932) but not broken until Roger Maris hit 39 from May-July 1961.
Maris' record stood until 1996, when Albert Belle slugged 40 homers from September '95 through May '96. Albert's record lasted for only a couple of seasons until McGwire and Sammy Sosa entertained us with their long-ball antics in 1998-99,
Who hit the highest percentage of their yearly homer total in a three-month slice? We have to exclude the slices that cross over seasons for this, but as Jack Lemmon said in The Apartment, that's how it crumbles, cookie-wise. The answer appears to Juan Gonzalez, who hit 74% of his 47 HRs in 1996 during his three-month slice (35 HRs from June 1-August 31). Reggie Jackson appears to be right behind him, with 72% of his 47 HRs hit in 1969 coming in the three-month slice of May 1-July 31. In third place: J.D. Martinez, who hit 71% of his 45 HRs in 2017 from July 1-September 30.
Stay tuned for more three-month slices...
