Commentary 
Many economists believe that during an economic slump, government should run large budget deficits in order to keep the economy going with increases in government outlays, with the consequent budget deficit giving individuals more disposable money. This, in turn, will result in an increase in consumer spending that will lift the economy’s gross domestic product (GDP) by a multiple of the increase in consumer expenditure.
For example, we assume that out of an additional dollar received, individuals spend ninety cents and save a dime. Also, let us assume that consumers have increased their expenditure by $100 million. Because of this, retailers’ revenue rises by $100 million. Retailers, in response to the increase in their income, consume 90 percent of the $100 million, so they raise expenditure on goods and services by $90 million. The recipients of these $90 million, in turn, spend 90 percent of the $90 million, or $81 million. Then the recipients of the $81 million spend 90 percent of this sum, which is $72.9 million, and so on….