A high rate of vacancies can indicate that an area is blighted or in decline, but it can also indicate a high number of vacation or seasonal homes, or an area with a lot of new construction where new owners have not yet moved in.

In 2015-19, 10% of residential housing units in the region were vacant, or about 54,500 units. This was less than the state and nation (both at 12%). The region's vacancy rate increased 2 percentage points from 2000 to 2015-19, a bit less than the state (up 4 points) and the nation (up 3 points). Monroe and Genesee counties had the lowest vacancy rate, both at 8%, while Yates had the highest rate (36%). As noted above, the high rate in Yates may reflect seasonal vacancies. In the City of Rochester, 14% of housing units were vacant, up 3 percentage points from 2000 but down 2 points from 2010-14. Since 2000, there were modest increases in the vacancy rates for most of the counties. Yates had an increase of 11 points over the same period.

The multi-year figures are from the Census Bureau's American Community Survey. The bureau combined five years of responses to the survey to provide estimates for smaller geographic areas and increase the precision of its estimates. However, because the information came from a survey, the samples responding to the survey were not always large enough to produce reliable results, especially in small geographic areas. CGR has noted on data tables the estimates with relatively large margins of error. Estimates with three asterisks have the largest margins, plus or minus 50% or more of the estimate. Two asterisks mean plus or minus 35%-50%, and one asterisk means plus or minus 20%-35%. For all estimates, the confidence level is 90%, meaning there is 90% probability the true value (if the whole population were surveyed) would be within the margin of error (or confidence interval). The survey provides data on characteristics of the population that used to be collected only during the decennial census. Data for this indicator are expected to be released in the fourth quarter.