Margin

The term crops up quite often in economics and finance. In the stockmarket, investors and analysts often focus on profit margins; the difference between the revenues from selling a product and the costs of producing it, often expressed as a percentage of the latter. Investors can also buy shares on margin; putting up only a fraction of the overall cost (an example of leverage). The marginal product of labour is how much extra output a firm would get by employing an extra worker, or by getting an existing worker to put in an extra hour. See also marginal cost, marginal propensity to consume, marginal tax rate and marginal utility.