By combining these dimensions of space, time and occupancy, very specific types of Utilization can be named.
The diagram below provides a reference for these Utilization types following a three-step naming process – choosing first the type of space measurement being used, secondly the basis of occupancy and finally the type of period. Note that each of these types of Occupancy can be addressed to specific types of Space, for example open-plan workstations, small offices, or meeting rooms, and care must be taken if multiple space types are included in a single statement of space measurement.
NOTE: Because measuring Space based on Resource Count or Capacity usually requires a known fit-out, it is normally not meaningful to state Utilization based on Allocated Capacity or Allocated Resource Count. This is because measuring the total amount of Space used as the denominator in the Utilization ratio is not well defined as the unallocated Space may very well be empty (no furniture and possibly with interior walls removed or reinstated), or at best the furniture and fitout may be arbitrary.
Assigned Utilization stated in terms of Capacity  has historically been the most common basis used in Utilization statements. This is largely because:
(a) it is readily available, as people need to be told where to work and assigned desks are often recorded in CAFM  systems;
(b) it is not volatile, because assignments do not depend on a person using a desk each day, and are not affected by holidays/PTO, or traveling; and
(c) when assignments do change, there are systems already in place that will be triggered by the change – even if not a CAFM system, then HR systems that identify joiners and leavers or internal transfers between offices or teams.
This type of Utilization is so common it has its own name, and so we formally define it here:
The ratio of the (Census of) Assigned Occupancy of a given Space to the Capacity of that Space
Note that the Assigned Occupancy of Space is also often talked about as a Headcount based on the criteria of who is assigned to the space. However, it is preferred to use the Assigned Occupancy of Space to make it clear that this is the group of people who are explicitly assigned to the space, and does not include other Headcount that nonetheless might use the space (for example visitors form other offices).