The value of labour power is expressed to workers as wages, to capitalists as profits. The rate of profit for an enterprise is the surplus value divided by variable and constant capital–roughly what today we call the rate of return on a company’s assets. The average profit rate of the economy as a whole is total surplus value divided by total variable and constant capital. But the size of the average profit rate depends on the composition of capital (how much variable and constant capital) and on class struggle–effectively, the size of workers’ wages relative to value produced.
