Batters: Lefty v. Righty "Plate Appearances"

This is the first of s series of posts to examine just how much of an advantage it is to bat lefty since that batters box is closer to all the bases.

Click this link to view gobs of data for seasons 1903 through 2012 and graphs that will be used.  More tabs with graphs will be added.  The annual data is from seanlahman.com and I used Microsoft Access to massage it.  Because Access does not deal well with fields that contain null values, plate appearances (PA) is generally simplified to at bats (AB) + base on balls (BB).  Values for Sacrifice Flies (SF) are null before 1954.

Here is the range of percentages for the seasons examined, excluding switch hitters, since their data is not broken down.

        Righty    Lefty
Min 58.49% 32.50%
Max 67.50% 41.51%
Ave 63.55% 36.45%

Max for righty batters was 1966, for lefties 1927.  Maybe Ruth and Gehrig influenced.

Here is the break down in recent seasons:

        Righty    Lefty
2000 63.74% 36.26%
2001 63.69% 36.31%
2002 62.35% 37.65%
2003 63.42% 36.58%
2004 62.75% 37.25%
2005 62.99% 37.01%
2006 65.65% 34.35%
2007 64.43% 35.57%
2008 61.86% 38.14%
2009 61.17% 38.83%
2010 62.96% 37.04%
2011 61.67% 38.33%
2012 60.42% 39.58%



The relationship has been pretty consistent for over a century.

Here is a graph, which includes switch hitters (Both).


        Righty    Lefty    Both
Min 51.34% 27.07% 2.57%
Max 63.71% 39.47% 19.99%
Ave 57.75% 33.16% 9.09%

The high for switch hitters was 1992.

For recent seasons:
        Righty    Lefty    Both
2000 54.91% 31.23% 13.86%
2001 54.39% 31.00% 14.61%
2002 53.26% 32.17% 14.57%
2003 53.32% 30.75% 15.94%
2004 52.41% 31.11% 16.48%
2005 53.09% 31.19% 15.72%
2006 55.62% 29.10% 15.28%
2007 54.37% 30.02% 15.61%
2008 53.30% 32.86% 13.84%
2009 51.34% 32.59% 16.06%
2010 54.04% 31.79% 14.16%
2011 52.88% 32.86% 14.26%
2012 52.18% 34.18% 13.64%