I have a free app in the Mac App Store. One day recently, I saw a strange 10x spike in "units" (free downloads) from Denmark. Sadly, there was no corresponding spike in in-app purchases. I saw a similar one-day spike last year but that seemed to come from the US. This one was entirely from Denmark. It only shows up on the "Sales and Trends" page. There is no matching spike on the app analytics page.
Has anyone else seen something similar? Is this something to be concerned about? There are lots of scams and frauds on the internet. I don't want any of those people taking an interest in me.
Mystery solved. This was a volume purchase. I contacted Apple Developer support and they suggested I download a summary report for the week and look for a BUS or EDU promo code. That was it.
As a side note, I've had two recent incidents of excellent and very fast responses from Apple Developer Support.