: 11 The later definition by Cavalli-Sforza & Bodmer (1971) is currently used: Genetic polymorphism is the occurrence in the same population of two or more alleles at one locus, each with appreciable frequency, where the minimum frequency is typically taken as 1%.
The financial world splits up its calendar into four quarters, each three months long. If January to March is the first quarter, April to June is the second quarter, and so on, though a company's first quarter does not have to begin in January.
Since a year contains exactly 12 months, that means that if you define your quarters in terms of months everything adds up. But if you define your quarter in terms of weeks there's a problemâ13 x 7 x 4 = 364 and a calendar year contains 365 (or sometimes 366) days. Consequently, a firm that defines its quarters in terms of weeks needs to hold a 14-week quarter every four or five years.