Specifies the length of time data should be continuously stored
in the same bucket. Modifying this value changes the time for
the current and future buckets. Previous buckets MUST NOT be
modified. Data in the current bucket MUST NOT be altered
either.
This object is only valid when etsysIpSlaConfigHistoryBucketType
is 'timed'. An 'inconsistentValue' return code is returned for
a set operation when the type is other than 'timed'.