This attribute is applicable and is displayed only for connections for
which the operational Tm abrConnectionType is displayed as
sourceDest, virtualSourceDest or explicitRate.
This attribute indicates the value of the Explicit Rate field from the
most recent Backward Resource Management (B-RM) cell on this
connection. This is the rate from the B-RM cell which may be
different from the explicit rate (ER) offered at this connection point.
Specifically, this attribute may indicate the ER which has been set in
the B-RM cell by some connection point before the B-RM cell
arrived at this connection point.