Measures the output compared to the inputs/resources used. For examples, labour productivity measures the amount of output produced by workers over a period of time. (= output/ number of employees)
Many marketing costs (such as adverting on TV) are fixed costs. When spread over a larger output or number of customers these costs are shared and unit costs fall
Larger businesses have a access to a greater range of sources of finance and can negotiate better terms and lower interest rates, leading to lower unit costs
Larger businesses can afford to employ specialist managers who are expert in their particular field, leading to greater efficiency and better decision-making, leading to lower unit costs