I'm looking into pulling reporting data about ARB subscriptions via the API, but I can't find a way to get a total of all successful transactions for a subscription.

The ARBGetSubscriptionList method includes the amount and pastOccurences fields, but pastOccurences is the number attempted, not the number successful, so that's not enough information to determine how much money actually changed hands. (If there was e.g. a successfulOccurences field, I could multiply that by the amount to get the total.)

What method(s) can I use to retrieve the total amount successfully billed to an ARB subscription?