s = N/AvgResYears x AvgSellMonths/12
The estimated number of units for sale is the number of total units divided by the average time people live in the units times the average months on market divided by 12. So for Oronoque village the estimate is
s = 900/10 x 5/12 or about 37. There are no surprises if 40 units are for sale. The question might better be looked at in the underlying numbers... Why is time of residence only 10 years? Ted gave the main reason -- this is a 55+ community and these folks are old. Add to that, many of these folks are snow birds and use the Connecticut condos as transition downsizing homes on their way to warmer climes; 10 years is an understandable number. Why 5 months for the sell cycle, which is a little long? The recovery of the condo market post 2009 real estate crash is slower than for purchased housing. So it's slightly long. But there is nothing odd or sinister in the number of units for sale.