How we worked this out.
- Their own sessions: session fee × average sessions per client.
- Referrals: the share who refer someone × the value of one more client. We count one round of referrals only.
- Over a year: the value of one client × 12, for one extra new client each month.
- This is what clients (or their insurance) pay your practice, before costs and tax. It's for comparing, not a profit figure.

