There is no per-stream rate. There is a licence, and the licence builds the pool.
Artist-facing explainers talk about as if a per-stream rate existed somewhere, set by someone. It doesn't. A (a digital service provider such as a streaming platform) can't play a without a licence from whoever controls it, usually a label or a . That licence is where the money is actually decided.
The licence answers four questions. What counts as the service's revenue? What may be deducted before anything is shared? What percentage of the remainder is payable to the licensor side? And what floors sit underneath the calculation if revenue per user falls? The answers define the divisible revenue pool: the pot of money that gets split across rightsholders in proportion to their share of streams.
That's why two services charging subscribers the same £11.99 a month can pay different effective rates. The price is public; the pool is contractual. An analyst's "effective per-stream rate" (what a licensor received divided by the streams that earned it) is an output of the licence, not an input anyone agreed.