Macro2Macroeconomic Data and Variables宏观经济学(南开大学,龚刚)

1、Lecture 2Macroeconomic Data and Variables,Macroeconomics,I. Macroeconomic Variables,Gross Domestic Product, GDP Definition： GDP is the total market value of all final goods and services produced by a country within a certain period (a quarter or a year).,I. Macroeconomic Variables,Gross Domestic Pro

2、duct, GDP (continued) The importance The variable reflects the economic activity level within a country. The so-called economic growth is referred to the growth in GDP. The so-called per capita GDP is often used for measuring the living standard of a country. It is perhaps the most important variabl

3、e in macroeconomics.,I. Macroeconomic Variables,Gross Domestic Product, GDP (continued) Here，the so-called final product is referred to those products that are not used as intermediate input. For example,. In addition, we shall also distinguish nominal GDP (calculated on current price) and real GDP

4、(calculated on fixed, base year, price).,I. Macroeconomic Variables,Price and Inflation Inflation is another problem that will be concerned in macroeconomics. Higher inflation may bring problem to the economy. The inflation rate is a measure of the degree of inflation problem. It is referred to the

5、growth rate of price level.,I. Macroeconomic Variables,Price and Inflation (continued) There are mainly three statistic indices to measure price level: GDP deflator; consumer price index; producer price index.,I. Macroeconomic Variables,Unemployment and Unemployment Rate The unemployment is another

6、important problem that is concerned in macroeconomics. Unemployment rate is the measure of the extent of unemployment problem. This is the ratio of unemployment to total labor force.,II. Some Stylized Factors, Evidence from Developed Countries,Why Important ? A proper macroeconomic theory should be

7、able to express the stylized factors as we observed from the empiric.,II. Some Stylized Factors, Evidence from Developed Countries,Economic Growth and Business Cycles An economy is generally in growth despite that sometimes GDP might decrease. The average growth rate of GDP is about 3% in current de

8、veloped countries. Economic growth often appears to be periodically cyclic. This cyclic property is often referred to be business cycles.,II. Some Stylized Factors, Evidence from Developed Countries,Figure 1: The growth rate in real GDP in U.S. 1961-2003,II. Some Stylized Factors, Evidence from Deve

9、loped Countries,Economic Growth and Unemployment Rate There has been a significant relation between economic growth and unemployment. Generally a high growth often implies low unemployment. This relation is often referred to Okuns law. It is named according to Okun, an American economist who find th

10、is relation empirically.,II. Some Stylized Factors, Evidence from Developed Countries,Figure 2: The Growth Rate versus Change in Unemployment Rate,II. Some Stylized Factors, Evidence from Developed Countries,Inflation and Unemployment If we observe the data before 1970s, we find a significant trade-

11、off between inflation and unemployment. Higher inflation often indicates low unemployment. This relation is often referred to Phillips curve. It is named after a British economist Phillips who find this relation empirically.,II. Some Stylized Factors, Evidence from Developed Countries,Inflation and

12、Unemployment (continued) This finding is once regarded to be a victory of Keynesian economics because it can be expressed by Keynesian macroeconomics it also provides a foundation for the effective application of Keynesian macroeconomic policy.,II. Some Stylized Factors, Evidence from Developed Coun

13、tries,Inflation and Unemployment (continued) However, when we extend our observation to the current period, we find that this trade-off become unclear. Such a deviation from the traditional Phillips curve also affect the debates among economists.,II. Some Stylized Factors, Evidence from Developed Co

14、untries,Figure 3: Inflation Rate versus unemployment, 1961 2003, US,II. Some Stylized Factors, Evidence from Developed Countries,Inflation and Unemployment (continued) Such a deviation from the traditional Phillips curve also affects the debates among economists. However, if we organize the data int

15、o three samples, we may find multiple Phillips curve. This indicates that the Phillips curve could be shifted.,II. Some Stylized Factors, Evidence from Developed Countries,Figure 4: Inflation Rate versus unemployment, 1961-1969，1994-2003,II. Some Stylized Factors, Evidence from Developed Countries,F

16、igure 5: Inflation Rate versus unemployment, 1970-1973，1984-1993,II. Some Stylized Factors, Evidence from Developed Countries,Figure 6: Inflation Rate versus unemployment, 1974-1983,III. National Income Account,There are two approaches to measure GDP The expenditure approach The income (or value add

17、ed approach) Theoretically, these two approach should give the same result,III. National Income Account,Expenditure Approach to Calculate GDP This is the way to calculate the GDP via looking at how the final goods and services are used. The GDP composition in terms of their usage: consumption invest

18、ment government expenditure net export (export - import) inventory change,III. National Income Account,Expenditure Approach to Calculate GDP (continued) Remark: The consumption, investment and government expenditure defined above includes the purchases on the imported goods. This is the reason why i

19、mport must be deducted from the export.,III. National Income Account,Income Approach to Calculate GDP This is the way to look at value added of all produced final output. Therefore it might also be called the value added approach.,III. National Income Account,Income Approach to Calculate GDP (continued),III. National Income Account,Income Approach to Calculate GDP (continued) The GDP composition in terms of value added: wage； profit； rent； interest； Others (e.g., depreciation).,III. National Income Account,Income Approach to Calculate GDP (continued) National Income: the income earned by the