This read-only Gauge32, in units of 0.01 percent, from 1 to 10000, represents the ratio of cumulative Codeword Severely Errored Seconds to Link Admin Up seconds, expressed as a percentage. An admin treats a rising value here as a more serious quality signal than a rise in the plain errored-seconds percentage, since severely errored seconds indicate heavier error activity. For example, an admin alerted by an increase in cwrPctSeverelyErroredSeconds would prioritize investigating that link over one showing only a rise in ordinary errored seconds.