What is the Marginal Efficiency of Capital (MEC)?

The Marginal Efficiency of Capital (MEC) refers specifically to the additional profit that results from investing in one more unit of capital. This concept is essential in understanding how businesses evaluate the effectiveness of their capital expenditures. When a firm considers investing in additional machinery, technology, or any capital asset, it assesses the incremental benefit, or profit, that this additional capital will generate compared to the cost incurred to obtain it.

This analysis helps businesses determine whether the investment will yield sufficient returns and justify the expenditure. By focusing on the extra profit produced by each additional unit of capital, firms can make informed decisions that optimize their investment strategy and overall economic performance.

The other concepts presented, while related to capital and profits, do not accurately capture the definition of MEC. Total profit from all units would encompass more than just the marginal effect, whereas profit thresholds and average returns do not specifically address the additional yield from the last unit of capital employed.