For sure we're undercounting. I had it and I'm not part of any official count because there's no way to get tested. My cohabiting girlfriend almost certainly had it, but she was entirely asymptomatic. Once you factor in all the asymptomatic people, in addition to all the symptomatic people who didn't end up hospitalized and thus likely couldn't get tested, the multiplier on the confirmed cases could easily be significantly more than 10X.
Pessimistically it seems that something like up to 10% of the city's population got it by the time that almost everything shut down, and now that almost everything is shut down, the spread has been vastly, vastly curtailed, as we see from new hospital admissions figures (which don't suffer from the same kinds of underreporting bias).
Pessimistically it seems that something like up to 10% of the city's population got it by the time that almost everything shut down, and now that almost everything is shut down, the spread has been vastly, vastly curtailed, as we see from new hospital admissions figures (which don't suffer from the same kinds of underreporting bias).