It looks like around 5% of Americans 65 and older live in “nursing home” environments.
I cannot find it again, but I thought I saw that around 25% of New York’s deaths were in nursing homes.
Looks like around 25%
...more than 2,300 New York nursing home and assisted facility residents have died from Covid-19, with another 2,500-plus presumed to have died from the virus, according to new state Department of Health county-level data. That’s more than five times as many coronavirus deaths reported in all of Washington state...
New York State Deaths 21,045 (as of today)
https://www.nbcnewyork.com/news/local/how-many-in-tri-state-have-tested-positive-for-coronavirus-here-are-latest-cases-by-the-numbers/2317721/