This setting is only used with the age filtertype, or
with the space filtertype if use_age is set to True.

The value of this setting will be used as a multiplier for unit.

unit, unit_count, and optionally, epoch, are used by Curator to establish the moment in time point of reference with this formula:

point_of_reference = epoch - ((number of seconds in unit) * unit_count)

If epoch is unset, the current time is used. It is possible to set a point of reference in the future by using a negative value for unit_count.

This setting must be set by the user or an exception will be raised, and execution will halt.