Originally Posted by
zymm
Another thing to look at within the US is the percentage of positive tests. That's actually rising right now, which is worrying since overall number of tests is also increasing. There are also data issues here, since different localities count differently (i.e. if one person is tested multiple times, do you count that as one person tested, or multiple tests?)
The other problem with percentage of positive tests is that it would presumably go down if way more people with no symptoms and no suspected recent exposure started getting tested. So, yes, if it goes up it's a bad sign, but if it goes down, it's hard to say what it means.