How many hair grafts can be harvested for an FUE procedure over a lifetime?

A typical scalp has 10-12000 hair follicles in the donor region. Typically a donor region has approximately 6000 grafts available for transplant before the donor region appears thin.

Each person has his or her own hair characteristics. Some people have skull and a large donor area's with high quantity of hair follicles. Typically these patients will have the most donor reserves;
Defining when a donor 'runs out' is a personal questions;Some patients will be ok with a moth eaten donor and see through effect.However most patients will halt further harvesting between 30-50% of the available grafts.
I believe the record for total amount transplanted is performed by several FUE procedure, adding up to 11000-12000 grafts.

FUE can harvest between 2500-5000 grafts without getting a depleted donor area provided that the hair is not super fine and the donor density is measures at least an average donor density. The coarser the hair the higher the number of FUE grafts in that range. The lower the donor density and the finer the hair, the lower the number of FUE grafts can be harvested.