Data from past experience usually provide the inputs to Equation 11-1. For professional employees, this cost can be staggering: 18 months' pay, according to the Hay Group, not
including lost sales and productivity (Lavetle,2003). Although this simple statistic is useful as a first
step, it falls far short of the cost information necessary for thorough advance planning and later evaluation
of the recruiting effort. In particular, the following cost estimates are essential: