Goods characterized by very high levels of subtractability and excludability. Subtractability means that one persons consumption of the good reduces the quantity available to others. Excludability means that the producer can restrict use of the product to those consumers who are willing to pay for it, while excluding those who do not meet this or other criteria. Private goods can be produced under private ownership or under public ownership. Except under special circumstances, for example, production in conditions of natural monopoly and where the government lacks the capacity to regulate, production of private goods increasingly is undertaken under private ownership.