Update: All of the Stadium Cards have been updated and can be found on this page.
The Stadium Cards released over the last fewl months have about 6-8 too many hit results on them. For example, these are the Old and New versions of Fenway Park for 1986:
If you look at the top of the right column on each table, you'll see that the old card has 8 more die rolls (666-673) that result in a hit. Eight die rolls out of 600 possible results doesn't seem like a lot, but its enough to drive up batting averages by about 15 points (e.g. pushing a league batting average from .265 up to .280). New Stadium Cards will be uploaded here before the end of the week (Friday, January 21st).
Fixing Existing Cards
If you've already printed cards (or purchased printed cards), the easiest workaround is to find 7 consecutive hits on your current Stadium Cards and change them to outs. For example on the above card you could change the rolls from 673-679 to outs. The type of out depends on how complicated you want to make things, but you could use the last digit (e.g., 673 = F3, 674 = F4, etc.)
If you're curious how this happened, I had bad data for Sacrifice Flies and Sacrifice Hits, and these numbers are needed to calculate the total number of plate appearances in each season. Again, this may seem inconsequential, but removing a few thousand plate appearances from the data changes things.