Calculating Service Level percentage from raw Analytics API interval data

Trying to understand how to derive Service Level percentage from the raw interval data returned by GET /api/v2/analytics/queues/{queueId}/summary. Raw buckets only yield answered.count, abandoned.count, and wait.seconds.sum, yet applying the standard SL formula against the intervalLimit ceiling breaks the pipeline.

The endpoint rejects custom aggregation filters and throws:

{
 "code": "badRequest",
 "message": "Aggregation type 'percent' is invalid for interval queries",
 "status": 400
}

How should the server-side calculation weight wait.seconds.sum before the SDK aborts the request?