NYC is a weird place to estimate in exactly this way. It has more of a lot of types of people who have pianos other than families. NYC has a disproportionate nu

NYC is a weird place to estimate in exactly this way. It has more of a lot of types of people who have pianos other than families. NYC has a disproportionate number of wealthy people, and also a disproportionate number of professional pianists, and I would expect both those categories get their pianos tuned rather more often than a typical family. NYC also has lots of concert halls, and any decent concert hall will tune the piano to be used in a performance on the day of. A hall like Carnegie hall would have several pianos tuned every day. I no do math, so maybe those things aren't enough to have a material effect on the number of piano tuners.