This table contains aggregated subscriber session performance
data collected for as much as a day's worth of 15-minute
measurement intervals.
This table has an expansion dependent relationship on the
csubAggStatsTable, containing zero or more rows for each row
contained by the csubAggStatsTable.
Observe that the collection and maintenance of aggregated
subscriber performance data is OPTIONAL for all scopes of
aggregation. However, an implementation should maintain at
least one interval for the 'scope of aggregation' that contains
all subscriber sessions maintained by the system.