Store Analytics API vs Partner Center: how is the "market" of an install determined?

Hello,

For our app AZERTY Global (Store ID 9N4BTS43SSSZ), from March 23 to November 4, 2026, the Microsoft Store Analytics API (installs endpoint) and the Partner Center Acquisitions report (Geographical spread) assign installs to different countries. Total installs are close, but the share of installs from African countries is about twice as high in the API as in Partner Center. The acquisitions endpoint of the same API gives an African share close to Partner Center.

Both documentation pages only define market as the country "where the install occurred" (Get app installs) or the "Country or region where installs occurred" (Acquisitions report).

How does each source determine the market of an install: the Microsoft account country, the device's Windows region, or the IP address? Before publishing the share of our installs by region, we need to know which measure reflects where the user is located.