"New York had 4,749 deaths as a result of influenza and pneumonia in 2018, according to the Centers for Disease Control".

NYC = ~50% so ~2400.

There have been 1867 deaths involving COVID-19.

The epidemic is currently 78% as bad as 2018 flu season.

https://www1.nyc.gov/site/doh/covid/covid-19-data.page

One could roughly estimate that 25-35% of NYC has contracted the virus going by comparing its relative deaths p/mn ratio to other regions like Lombardy, Colorado and Brussels where samples of infection rates have been taken.