This Counter64 counts frames received at ingress that were discarded outright because they exceeded this circuit's traffic contract beyond even the Excess Burst (Be) allowance set in circuitFwdTDParam3 -- meaning these frames weren't just tagged, they were dropped entirely. A steadily growing count here is a direct, concrete sign that this circuit's actual offered load exceeds what its provisioned CIR/Bc/Be parameters allow, and traffic is being lost as a result, not just marked. For example, an admin seeing this counter climb consistently would consider either raising circuitFwdTDParam1 (CIR) to match real demand or working with the traffic source to reduce its offered load, since every increment here represents data that never made it onto the circuit.