(3) monetary benefits -- increase the monetary value of assets. There are both measurable and unquantifiable benefits in these three different forms of income. Among them: mental income is too strong to measure, monetary gain is easy to measure because of the static concept of value change. Economists, therefore, focus only on actual earnings. Historically, the concept of income has first appeared in economics. Adam Smith, in the wealth of nations, defined income as "the amount of consumption that is not eroded by capital", and saw it as an increase in wealth. Later, most economists inherited and developed this view. 1890, ai (Alfred Marshall Maarshell) in its "the principles of economics," the Adam Smith's "wealth increase" enterprise, introduced the concept of earnings, is proposed to distinguish the entity capital and value-added benefits of economic benefits. It is also worth noting that in 1985, the financial accounting standards board released the concept of income from the concept framework (SFAC)NO. 6. In 1989, the international accounting standards board's framework for preparing and providing financial statements made clear that benefits also included unrealized gains. In 1997, FASB's FASB N0.130 required a full return; In 1998, IASC's IAS NO.1 required the preparation of an equity change table, a comprehensive income statement, including the benefit of reflecting corporate assets. Historical costs differ from current values He added: "austerity has failed and will only continue to undermine our economy in the brexit negotiations. Although interest rates are expected to rise further next year, savers should not expect higher interest rates from Banks, experts have suggested. According to the engine displacement, divided into a miniature (1 liter), light level sedan (1-1.6 liters), intermediate (1.6-2.5 litres), senior sedan (2.5 4 liters), limousine (4 liters).