Customer equity is

simply the financial result achieved by a single marketing strategy.

the total difference between the benefits of a firm's whole marketing program and total costs of obtaining those benefits, as the group of target customers sees it$.$

increased when a firm is able to increase the earnings stream expected from current or prospective customers.

decreased whenever the firm's costs of offering a marketing mix increase.

the difference between the benefits of a firm's marketing mix and the cost of obtaining those benefits$--$as a particular customer sees it$.$