 The percentage BV of egg protein is only 93.7% which allows other proteins with true percentage BV between 93.7% and 100% to take a relative BV of over 100.For example, whey protein takes a relative BV of 104, while its percentage BV is under 100%.The principal advantage of measuring BV relative to another protein diet is accuracy; it helps account for some of the metabolic variability between individuals.