Average variable costs (AVCs) first fall and then rise, as illustrated in Figure 5.5b. As
the TVC curve was the inverse shape of the TP curve in Figure 5.4, AVC is the inverse
of the AP curve. That is, as the average productivity of labour (AP) rises, then average
labour costs (AVC) per unit of output must fall. When AP is maximised, AVC is at a
minimum. As AP falls, AVC rises.