1000 minute/month ...

I can't speak to whether our use is typical or not - but we tend to do things in clusters. So, currently, we have about 24 hours of material that need editing. Also, keep in mind that sometimes we have to do a session a 2nd time - so it adds to the amount of time.

3 to 5 months could go by where there is little or no transcribing going on. The average over the course of a year would easily be below 1000/month. Perhaps this is something that can be monitored in your pricing policy.