Now, however, that wisdom is being questioned, not just in Britain. As long as inflation is a real and present danger, it makes sense to put monetary policy down to the conservative central bankers and keep them from the government's fiscal deficit. Instead, the problem today is the opposite: that the central bank cannot raise inflation to its target. Generally speaking, the interest rate varies according to the term of measurement, indicating that the method has annual interest rate, monthly interest rate and daily interest rate. This week, interest rate debt in developed countries in Europe and the United States suffered a massive sell-off. Affected by this, the yield curve of government bonds has been changed to a steep and steep trend. A CBI survey of 109 companies this month found that online sales of black Friday and cyber Monday were "unremarkable". 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.