Headcount capacity
Headcount capacity estimates what a team can deliver from the number of people in it, multiplied by a standard period of hours. Ten people at a forty hour week gives a nominal four hundred hours. The figure is a ceiling nobody reaches, and it is useful only if read that way.
The estimate has one virtue. It needs no data. So it is the first number anybody reaches for, and the one most often pushed past its usefulness.
Everything real takes a bite out of it. Leave. Holidays. Hiring, internal work, the support rota, the meetings that keep a team in step. None of that is waste, and all of it comes off the top.
Plan a year close to the nominal figure and you have planned a year that will not happen. The gap is not slack waiting to be won back.
Its honest use is a check at the top. If the nominal number is already smaller than what has been promised, no planning detail will save it. What is needed then is a talk about scope, not a better spreadsheet.
Measure your own gap instead of borrowing one. Take a few finished months, compare the nominal figure against the hours that were really logged to client work, and keep the ratio. It ages slowly and it beats any rule of thumb you could read somewhere.
Where this shows up in PeopleMuster
PeopleMuster shows a monthly planned total per person on the capacity grid, built from allocated days rather than from a headcount multiplied by a standard week.
Questions people ask
How far off is nominal headcount capacity?
Materially, and the gap differs by firm. Leave, holidays, internal work and coordination all come off it. Measure your own gap over a few months rather than assuming a general figure.
Is headcount capacity ever the right measure?
As a first check at the portfolio level, yes. If commitments already exceed the nominal ceiling, the problem is scope and no scheduling detail will resolve it.
How does headcount capacity relate to available hours?
Available hours are what remains after absence and commitments come off. Headcount capacity is the figure before any of that, which is why one is planned on and the other is not.