This is a very quick hit, just to push a semi-vagrant thought out there for future examination.
Here we have the percentage of singles that occur on the infield. Not just bunt singles, which are a much smaller subset of infield singles, but all batted balls that remain in the infield. (Yes, that means bunt singles are included in the total.)
We're expressing it here as (infield singles/total singles), and we are breaking it out by age range (our usual age range choices: age 25 and younger, 26-29, 30-34, 35 and older).
You're probably not going to be particularly surprised by the pattern of the percentages.
The difference between the AL and NL can probably be summed up in one word: pitchers. Particularly pitchers over 30.
We'll run this data again without the pitchers and see how the age ranges look with that adjustment.
It will also be interesting to take this data back through time.
But not tonight!