Runners on Base?

Still playing around with the offensive numbers from 2007. An interesting question popped up in my head and that was what sort of percentage of runners that get on actually score. So once again went to baseball reference and dug though the season and looked plate appearances, at bats, runs scored, hits and walks (hit by pitch and reached on error), and left on base numbers. What I found was utterly fascinating to me and that is how the averages for each month of the season were so close. Over 24 - 29 game span each month, the plate appearances, at bats, hits and walks, and left on base were remarkably the same.

AVERAGE	G	PA	AB	R	H+BB	HBP+RE	LOB
April	26	40	34	4	13	1	8
May	28	38	34	4	12	1	7
June	27	40	36	6	14	1	8
July	24	39	34	6	13	1	7
August	29	41	36	6	14	1	8
Sept	29	41	36	6	14	1	8

I then plotted the running percentage of a few of these factors versus projected wins just to see which number means most to a teams wins. Again the number that wowed me was that Left on Base per Plate Appearance (blue line above) which indicates that on average the Roxs pretty much consistently left 8 runners on throughout the season. Almost no change.