Economics and the 2008 crisis: a Keynesian view

Short run average cost (SRAC) curves (2)

It’s often easier to represent cost curves graphically. Here the two columns of data in Table 4 are shown in separate graphs. The table is repeated below.

Figure 34 Total cost and average cost curves

Quantity of output (units) Total cost (£) Average cost (£/unit)
1 2000 2000
2 2800 1400
3 3400 1133
4 4000 1000
5 4750 950
6 5800 967
7 7200 1029
8 9000 1125

Notice that total cost increases with output, albeit at varying rates. The SRAC captures how average cost (or unit cost) changes with output. When output is low, initially average cost falls, but as output increases, average cost starts to rise. Next let’s examine the components of average cost – fixed and variable cost.