Stakeholder pensions (& no. of employees)

The threshold for having to provide a stakeholder pension is ‘5 employees’ – does this mean individuals or FTEs?

I’m a trustee of a charity that currently employs three part-time staff. If we get a lottery grant that we have bid for, we will need to take on additional staff: one full-time and two more part-time.

This will mean 6 individuals employed, but only 3.5 FTEs.