In equation (2) the chosen benchmark is the male rate of return (pm), but it would be equally plausible to use py as the benchmark set of coefficients. As the choice between these two alternatives may appear somewhat arbitrary and can give rise to differences in the results of the decomposition, a widely used alternative is to calculate a benchmark coefficient p' from a pooled earnings regression over the joint sample of male and female workers (Neumark, 1988). Data refer to regular employees for India.