Expert: Tom Schott - 6/23/2011

Question
What is the percent of all runs scored by home runs to total runs scored?  Is there an historical stat on this somewhere? In an earlier post you gave the percentage of total home runs to total hits, but that does not indicate the runs scored.

Thanks

Answer
Mike,

 The percentage of runs that are attributable to HRs . . . this question is going to take some digging. To my knowledge there is no such stat immediately available. But we can work on it. What I have to do is figure out what percentage of HRs are hit by on-base situation, i.e., one on, two on, etc. Right now all I can give you is the percentage of runs scored by the guy who actually hit the home run. I arrived at this number by dividing the total number of HRs by the total number of runs scored in a given year. I just arbitrarily selected the years ending in zero since 1900 as representative years for each decade, and I figured only the National League. I could have selected any year. Obviously, I don't have time to do the entire history of baseball. The results are nonetheless suggestive.

Percentage of Runs Scored by Hitters of Home Runs in the NL and (AL), 1900-2011

1900  4.3  
1910  4.3  (3.2)
1920  5.3  (6.3)
1930 12.7  (10.1)
1940 12.7  (14.4)
1950 19.1  (15.6)
1960 19.8  (20.1)
1970 19.2  (21.5)
1980 15.8  (18.1)
1990 18.6  (17.9)
2000 23.2  (22.4)
2010 21.4  (21.9)
2011 20.4  (21.3)

The raw numbers for these calculations can be found at:

http://www.baseball-reference.com/leagues/NL/bat.shtml   NL
http://www.baseball-reference.com/leagues/AL/bat.shtml   AL
 
I see a consistency here, don't you? Except for bulge in 2000--the steroid era. My guess is we're going see this same consistency when we get all the numbers.

Please post your question again in 3-4 days, and I will see if I can come up everything you're looking for then. Thanks.