I. That Confounding Census
The Greenburgh townwide population increased from 88,400 in the 2010 census to 95,397 in the 2020 census - that's 8% growth.
This increase, however, starts to seem puzzling when examining other data. For example, according to the 2020 census, occupied housing units in the town increased by 2,281 since 2010 to 35,776 townwide (1,789 units apparently are vacant). These 7000 additional residents have to live somewhere, and with relatively few new housing units, the town saw an increase from 2.64 residents per housing unit in 2010 to 2.67 per unit in 2020.
Maybe there's a baby boom and families are growing? That's not the case as the census also shows that the population growth is entirely among residents aged eighteen and over, who increased by 6,897 turning the same time period. In fact, in each of the six villages, as well as TOV, the percent of the population that is 18 and over stayed the same or increased.
And it gets weirder when looking more closely at some of the village housing numbers. Hastings' population increased by 741 but the village's housing units only increaed by 28 total. Tarrytown, conversely, has 583 more residents but also 345 more housing units.
We have another source of data independent of the US Census that can be helpful: school enrollments collected and vetted by the NY State Education Department annually. We know that in the 2019-2020 school year, there were 17,669 kids in Greenburgh enrolled in K-12 school programs, including public, private, parochial and even 38 kids who were homeschooled that year. As far as 2009-2010, we can find that 15,857 kids were enrolled in public schools, but we don't have the private school numbers. Why not just match up public school numbers across decades? That's not a great data point because close to 10% of Greenburgh kids typically attend non-public schools. However we do know that in recent years, nonpublic school enrollment has been dropping town wide. The closest school year nonpublic enrollment number to 2010 that I can find is from 2013-2014 when 1,815 kids townwide were enrolled in nonpublic schools. This approach is far from perfect, but using the 2009-10 public (15,857) plus the 2013-14 private (1,815) gives us 17,672 K-12 kids townwide. This just happens to match nearly exactly the 2019-2020 K-12 number of kids townwide of 17,669. Yes, there are assumptions being stretched, but it seems likely that over the past decade there has in fact been no increase in the school age population townwide.
So where do we stand?
1. Greenburgh population as reported by the US Census grew by 7,000 from 2010 to 2020.
2. That growth appears to be entirely in adults as
a. the census shows almost 7,000 additional residents in 2020 who are 18 or over,
b. the census shows no growth in under 18 year old population from 2010 to 2020
c. school enrollments townwide do not appear to have increased from 2010 to 2020.
3. This growth is confounding as it makes little sense that the adult population grew 10% while the child population (under 18) would show zero growth.
4. It seems bizarre that the town would grow by 7,000 additional adults (with no increase in children), but add only 2,281 housing units during the past decade. Are these adult tripling up? Is Greenburgh that progressive?
At this point, it would not be crazy to ask if the 2010 census is reliable: did it undercount? A possible explanation comes from voter enrollment numbers. Voter rolls are very unreliable as a measurement of population because the rolls are not regularly updated as voters move away or pass on. However, we can see trends and we do see from the county Board of Elections that registered voters in Greenburgh (both active and inactive) increased from 2010 to 2020 by 5,162. This is only speculation but maybe the 2010 census undercounted a couple of thousand residents resulting in an actual adult increase of 5000 or so, who will fit more comfortably into those 2181 additional housing units?
II. DELTA VARIANT PLATEAUING (FOR NOW)
After increasing by one hundred active cases in ten days, active cases townwide settled at 249 as reported on August 22, close to the total (249) from August 15. Has the Delta Variant wave, which took the town from 31 active cases in mid-July to 260 in mid-August, crested?