trkAtmLastCalculatedTxVccUtilization 1.3.6.1.4.1.562.2.4.1.60.3.15.1.2

This attribute indicates the last calculated transmit utilization of the ATM VCC. It is calculated every 30 seconds based on comparing the number of cells transmitted by the AtmIf Vcc with the estimated available bandwidth on the AtmIf Vcc.