I was asked what the percentage of runs scored in baseball throughout a season are due to homeruns. I have all the data I need except one piece - What is the average number of baserunners during a homerun? I am sure most HR’s are solo, so I anticipate the number to be somewhere in the 1.5-1.9 range, but that’s a big range.
Does anyone have the Straight Dope on this?
I don’t know the answer to your question, but there was a book published a few years ago called The Home Run Encyclopedia. It’s out of print and a bit out of date now, but it did break down homeruns by players by number of men on base. If you can find it in your library or in a used book store, it should answer your question.
Zev Steinhardt
Correction: The book is in print and available on Amazon.com
Zev Steinhardt
The average number of runners on base per home run is likely to be less than one.
If each of the four possibilities, zero thru three, were 25%, then the average would be 1.5 runners. But grand slams are uncommon. Take a look at this page:
http://cbs.sportsline.com/mlb/history/records/season_batting_GSH
You will note how extremely few times anyone has hit as many as four in a season.
I didn’t bookmark the page, but another I found stated that in the All Star Games there had been 154 homers - 89 solo, 51 with one on, 13 with two and only one grand slam. By my calculations, this works out to .506!!
I miswrote my question. When I said 1.5-1.9, I meant runs scored per HR, not runners on base per HR.
Thanks for the correction!
However, the all star game probably isn’t a perfect benchmark. Because it is an exhibition, intentional walks to load the bases are less likely, runners are more likely to be sent on risky plays, and hit and runs are less likely, making double plays more likely.
Just to prove what a geek I am, Fred Lynn hit that grand slam in 1983. I can still remember it.
The general rule throughout history is that 1.5 runs per homer is a good guess. It’s probably a bit higher today, with on base percentages higher than they used to be. The average team hits about 160 home runs a year, so that’d be 240-270 runs depending how lucky they got, or about a third of all runs.
Well Lou Gehrig with 23 grand slam home runs 73 three-run homers and 166 two-run homers out of his 493 holds the record for RBIs per homer for anyone with over 300. This works out to 1.78 RBIs per homer.