Managers should consider several factors when forecasting personnel needs. The usual process is to forecast revenues and then, from that, estimate the size of the staff required to achieve this sales volume. However, in practice, the manager will need to consider other factors as well, such as projected turnover (resignations or dismissals), decisions to upgrade (or downgrade) products or services, technological changes, and the department’s financial resources. In any case, managers use several simple tools for projecting personnel needs, as follows.