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Members - Otherwise known as ‘headcount’ which is the physical number of people allocated within the team.
FTE - The total available capacity of a person that can be allocated into a team.
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For example:
Bob as a person is 1 headcount but he works part-time therefore his available FTE / capacity that can be allocated out is 0.8 therefore creating a difference between the two values.
What’s the difference between the two different FTE values shown against a team?
eg: In the photo above we see 230.74 FTE / 239.93 FTE:
230.74 FTE - This is how much of the available FTE has been allocated into this specific team.
239.93 FTE - This is how much available FTE that can be allocated into this specific team.