We have contribution stats on AMO: https://github.com/mozilla/zamboni/blob/master/apps/stats/views.py#L406 This gives us date purchase, number of sales, total sales, average sale price. We should move this to Marketplace: https://github.com/mozilla/zamboni/blob/master/mkt/stats/views.py#L59 And we should also add purchase type (app sale or in-app), number of refunds, and currency. We can throw this in elasticsearch, as currently this is taken care of by ORM calls.

We'll want to add permission checks (à la https://github.com/mozilla/zamboni/blob/master/apps/stats/views.py#L288) and add tests (à la https://github.com/mozilla/zamboni/blob/master/apps/stats/tests/test_views.py#L120).