Thanks for your fast response!
Yes, I moved some content while setting up a new blog. Maybe I copied also the database (I tried so much I don`t even remember ;-) ).
In the end I decided to start up the new blog with new content and leave the old blog where it is (on the subdomain).
But now my new blog shows me the stats of the new visitors but also all the visitors who were on my old blog (on the subdomain…).
Is it possible to clear the whole stats? To start from zero?
Where do the stats come from? Is Jetpack getting them from the Database or from the Server?
Thx & greetings from munich!