[vonmoltke]

> I think only South Korea is the other country with extensive testing.

South Korea has tested a tiny fraction of their total population, because the testing is largely targeted via contact tracing.

[yters]

It isn't about proportion of population, but whether they are only testing people already admitted at the hospital, which will drive the estimate up, or testing the wider population, driving the estimate down. SK is doing the latter through contact tracing.