Look up population
Derive percentage
https://www.google.com/search?q=nyc+population says 8.4M
https://www.google.com/search?q=corona+death+toll+nyc says 10k
https://nypost.com/2020/04/18/nyc-coronavirus-deaths-near-13... says 13k
This gives 0.1%. The OP's numbers are based on 6M population & 15k deaths. I believe their trying to cite total deaths, not just covid-19 related. Their NYC region also seems to be more localized