For any other math people out there (and to answer your question,

Blade), I decided to run a few independent samples t-tests, grouping data from before the fourth quarter of 2012 (so, 1/12, 2/12, and 3/12) and after (4/12 &1/13). Using

Blade's calculations, I analyzed whether there was a statistically significant difference in the proportion of girls to boys, proportion of multiples to singletons, excess girls (observed/predicted), and excess twins (observed/predicted). I didn't really expect to find much since our sample size is so small, but

**there was a statistically significant difference in the amount of excess girls (t(3)=-5.45, p<.05)!!! Specifically there was a smaller proportion of observed/expected girls in and after the fourth quarter of 2012 (M=1.30, SD=.02) than before (M=1.44, SD=.03).** So...good work team sleuths!! Maybe as our sample size grows we'll find more statistical differences!!