Description: The number of times an subnetMatrix entry has been inserted into the subnetMatrix tables. If an entry is inserted, then deleted, and then inserted, this counter will be incremented by 2. The addition of a conversation into both the xsSubnetMatrixSDTable and xsSubnetMatrixDSTable shall be counted as two insertions (even though every addition into one table must be accompanied by an insertion into the other).To allow for efficient implementation strategies, agents may delay updating this object for short periods of time. For example, an implementation strategy may allow internal data structures to differ from those visible via SNMP for short periods of time. This counter may reflect the internal data structures for those short periods of time. Note that the sum of then xsSubnetMatrixSDTable and xsSubnetMatrixDSTable sizes can be determined by subtracting xsSubnetMatrixControlNlDeletes from xsSubnetMatrixControlNlInserts.