Description: If retransmission is not used in a given transmit direction, this parameter reports the previous net data rate the bearer channel was operating at just before the latest net data rate change event occurred, excluding all transitions between L0 state and L1 or L2 states. If retransmission is used in a given transmit direction, this parameter reports the previous Expected Throughput(ETR) (as defined in G.998.4) the bearer channel was operating at just before the latest ETR change event occurred, excluding all transitions between L0 state and L1 or L2 states. The data rate is coded in steps of 1000 bit/s. The invalid value is 4294967295. If data on the port is invalid or no data is generated on the port because the port has not been activated, the invalid value will be returned. Unit: bits/second