Resolving the Shidduch Age Gap Theory Debate

Excellent new data provides a clear and unambiguous conclusion

NOTE: This article has been updated to include content that incorporates a larger dataset from the one the original version was based on.

I know that I’ve written about this topic more often than might be wise (here, here, and here), but there’s just been a significant update.

As I noted a few months back, data professionals Channah Cohen and Akiva Friedman used government demographic data covering Lakewood NJ to project population trends in that Orthodox community. They concluded that there is no significant difference between the numbers of 19 year old girls and 23 year old boys. Based on the actual numbers of boys and girls there should, in other words, be no shortage of 23 year old boys for all the 19 year old girls to marry.

I felt - and continue to feel - that their methodology and conclusions were sound. But their source numbers could still be questioned as, after all, they were still just a proxy for our actual population.

However, I just discovered a treasure trove of data from the Private School Universe Survey provided by the US National Center for Education Statistics. Their site allows me to search all private schools in a geographic area and filter for religious affiliation. So I no longer need to focus exclusively on Lakewood’s 08701 and artificially control statistically for its non-Jewish population. And, because I can also filter for male-only and female-only schools, I now have extensive data on every single Orthodox school in the area.

The point is that I now have a statistically significant dataset representing nearly 85,000 1st to 12th grade children from Orthodox families. The data covers pretty much all NY (downstate), NJ, and PA schools.

Ok. Enough talk. What does the data actually show us?

Between 1st and 12th grades there were, in the 2020-2021 school year, 39,980 girls and 45,254 boys. That’s weird, as there are more than 11% more boys than girls. You’d normally expect a 105:100 boy/girl birth disparity across most populations. But 11% is hard to believe. Worse: there are more than 22% more 1st grade boys than 1st grade girls across all schools.

I can’t explain this, but I can say that most of the “problem” for the early grades can be traced to Queens. I hope to figure out what’s going on there some other time.

There’s something else. For boys - and not girls - the numbers plunge between 9th and 12th grades. There were, in fact, only 2,199 boys across the whole system by 12th grade (compared with 2,916 girls). I don’t believe this has anything to do with natural population growth.

Instead, one possible explanation is that, from the 9th grade, many chassidishe and uber-yeshivishe boys are removed from formal schooling in favor of all-Torah programs and are, consequently, not counted in this survey. To account for that, I’ll ignore all numbers above 8th grade and focus exclusively on the lower grades.

We can accurately identify population growth (or decline) by examining changing grade cohort numbers. So the fact that there were 4,792 boys in 1st grade and only 3,897 in 8th grade tells us that the number of boys born in 2016 was 19% greater than those born in 2009. That indicates male population growth at an average annual rate of 2.6%. The corresponding growth rate among girls was 1.7%.

Here’s what those numbers looked like:

Not only are there more boys than girls in each grade but (as the “Male Surplus” column shows) there are more boys than the girls who are three years younger! That means that in around 13 years - when the current crop of female 1st graders starts going out - there will be a significant surplus of boys (472, to be exact).

Unless I’ve missed something, I believe that this is the last word on this subject. From here on in, our concern should lie with figuring out how to help all singles find their shidduchim.