Changing Dynamics of HR and SB Distribution in MLB

and their implications for fantasy

Last time, we looked at how broad level statistical changes might be affecting fantasy values in the pitching pool. This post will examine some trends on the hitting side. As it relates to fantasy baseball, the significant recent changes relate to the Home Run and Stolen Base categories. Let’s look at some data on each.

If you have been following MLB news over the offseason, one of the major storylines has been how poorly the big sluggers have done in free agency. Last year’s AL home run leader, Mark Trumbo, twittled his thumbs on the free agent market for months before eventually resigning with the Orioles for much less money than he was hoping for. 2016 NL home run co-leader, Chris Carter, lingered even longer, nearly having to take his 3-true-outcomes game to Japan before finally finding a paltry (it’s all relative, man) $3 million deal with the Yankees. Edwin Encarnacion, Jose Bautista, and Brandon Moss all had to settle for much less money than they were seeking. The implication is clear: major league teams are not digging the long ball anymore. The reason for this also seems clear: if an undersized middle infielder like Freddy Galvis can knock 20 balls out of the park, why shell out the big bucks for a hulking slugger? So, does the data support this change in philosophy among major league front offices? The data indicates, yes, at least to some extent.


The above table puts hard numbers on the chatter we’ve been hearing about the home run spike in baseball. Whereas in 2014, when pitchers seemed to rule the world by limiting home runs to a generational low (4186 HR to be exact) the past two seasons have seen an explosion in HRs to levels not seen since the steroids heyday (5610 in 2016, second only to the 5693 dingers in 2000). That’s a 34% increase in HR in just 2 seasons for those of you keeping score at home.

That kind of change in and of itself is something all fantasy players should be aware of, but what really matters in the fantasy game is how those extra HRs are distributed. If all hitters up and down the value ladder are increasing their homers at the same rate, then fantasy values are not too strongly impacted. But what we saw in 2016 was a sort of democratization of home runs; they were spread out somewhat more widely across the player pool. Whereas the top 30 home run leaders in MLB accounted for 21% of all HR hit in 2014 and 2015, the top 30 only accounted for 19.5% of all HR hit in 2016. That may not be an earth-shattering change, but it represents the lowest share for the top 30 in the 17-season time period examined here. With home runs spread out more widely throughout the player pool, the top sluggers, especially the one-dimensional guys who offer no speed and who act as a batting average anchor, are becoming less valuable in fantasy baseball, just as they are in the real-life game.

Turning our attention now from the power game to the speed game, let’s see how stolen base trends may be making an impact on fantasy baseball. As you can see in the chart below, stolen bases have declined significantly over the past four seasons from their peak in 2011-2012. Whereas there were 3279 SBs in major league baseball in 2011, by 2015 that number had dipped down to a generational low of 2505, a decrease of nearly one-quarter (SBs increased ever so slightly to 2537 in the 2016 season). Recent seasons have also seen a modest upward distribution in stolen bases, as the top 30 basestealers in MLB accounted for only 30.2% of all SBs in 2012, but by 2016 had increased their share to 35.2%.


To summarize: home runs are up significantly the past couple seasons and have been spread more evenly across the player pool. Meanwhile, stolen bases are sharply down and the top basestealers are accouting for a greater share of all stolen bases. The distributional changes are what’s really key here, and although they may not be dramatic (21% to 19.5% for HR leaders; 30.2% to 35.2% for SB leaders) they are certainly noticeable and significant. When combined, these trends clearly indicate that top speed guys are gaining value in fantasy baseball relative to power hitters. Just as I argued in the last post that workhorse starting pitchers are now worth a buck or two more than they would have been in seasons past, it seems evident to me that the top speed burners are also worth an extra buck or two heading into the 2017 season than they would have been before the recent changes to the MLB hitting environment. Historically, I have shied away from the speed-only guys, preferring to fill my roster with players who can contribute across multiple rotisserie categories. But this might be the season where I take the plunge and spend what is necessary to roster the likes of Billy Hamilton, Dee Gordon and Rajai Davis.