How many have mild or assymptomatic? 20k? 100k? a million? You have no idea, but it could be a huge amount. The only people that come in for treatment are those with serious symptoms.
That is true but unless the serology is performed on at least 10% of the pop we have no idea. However there is a difference between current asymptomayic and asymptomatic recovered. Recovered are immune. Current are infectious.