Reliability is calculated using the following formula:
reliability = number of errors / number of total frames
Referring to Load-interval
The length of time, in seconds, used to calculate the average load on the interface. Valid values range from 30 to 600 seconds, in multiples of 30 seconds. The default is 300 seconds (5 minutes).
Modify the default to shorten the length of time over which load averages are computed. You can do this if you want load computations to be more reactive to short bursts of traffic.
Load data is gathered every 5 seconds. This data is used to compute load statistics, including input/output rate in bits and packets per second, load, and reliability. Load data is computed using a weighted-average calculation in which recent load data has more weight in the computation than older load data.