Pretty sure the error modifiers aren't working as noted in thread here:
http://forums.ootpdevelopments.com/s...d.php?t=345128
While the % change does not seem drastic, due to the way fielding % is calculated the difference in 1908 for example is 1 baserunner per game. That's not the whole cause obviously, but would appear to be one cause as the fielding % is pretty much constant in the screenshot which does not align to historical events.