For “as hatched” flocks, the calculation of uniformity using a single criteria such as (C.V. or % at ± 10%) is not very reliable, as the birds become older, due to the predominant dimorphism on uniformity between the sexes. As an example, the above graph shows that a flock of Label broilers is made up of two very uniform populations, although the C.V. of the flock is quite high (14.3%).