an apparatus and method for generating via integer calculations a metric for estimating link utilization within a network device having at least one output port . the metric is determined by calculating at least three data rate link parameters for a given sampling period . the data rate link parameters include an error data rate parameter , an average data rate parameter , and a deviation data rate parameter . these parameters are determined using integer values and integer operations and may be used by a link management system for performing load balancing among a plurality of output ports and for determining whether to forward low priority data traffic via a particular output port .