SJSinNYC
Re the ratio of boys to girls the ratio ranges between 103 and 107 makes per female. Among non hispanic whites in the us the rate is about 105 to 100. Yes it is “Possible” that for some reason orthodox jews have a ratio skewed towards women but in the absence of any evidence I don’t think this is something we have to be concerened about.
Incidentaly there was a study done in Israel examaning the ratios among “Charedim” – the numbers where more or less the same as white americans.
The ratio of boys to girls is declining but it is in the order of 1/10th of a percent over decades – not a factor that need concern us.
Re going off the derech it is important to make the distinction bet GOTD as it appllies to schools and GOTD as it applies to marriage. In my experience – correct me if I am wrong – most boys who GOTD end up marrying whithin the orthodox commmunity. To the best of my knowledge there really isn’t any hard evidence re the ratio of boys to girls going off the derech.
One note about the math – when calculating the growth rate taking into account boys GOTD the 6% is subtrated after deriving up the the ratio of boys to girls.