App Store Commission for Developers

We are planning to release an app on the App Store. I have a few questions about the commission that Apple demands from Developers.

  1. When I discount an app subscription, is the 30% commission calculated from the full price or the discounted price (i.e. from what a user will actually pay)?

  2. Where are these numbers written down? I cannot seem to find an agreement from Apple where these 30% percent are actively mentioned. Just answers from forums, nothing official.

App Store Commission for Developers
 
 
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