Use of Index Numbers

Index Numbers

Index numbers are used by economists to both represent and to understand economic data in a much clearer way. Economists typically report price levels in each period as an index number, rather than a dollar amount.

Index numbers

Economists create price indices to calculate an overall average change in relative prices over time.
- E.g. if you were told the average price of housing in the US was $256,010, and it is forecast to rise to $268,221, it is hard to process this data. But if you were told the index level was forecast to rise from 107 to 110, you would have a better idea of the significance of this change.

How to calculate an index number

You need to choose a "base". This is commonly a year but doesn't have to be.
It is the “thing” that everything else is being compared to.
- E.g. if the base year is 2008, then the index number in 2009 is being compared to 2008, the chosen base year.
It is convention to set the base year index number equal to 100.
To calculate an inflation rate we use the following formula: (New value / Base year value ) x 100.

Example of calculating an index number

In this example, 2015 has been chosen as the base year, with an index value of 100.0.
To calculate the index value in 2016, the calculation is ($257,111 / $250,010) x 100 = 102.8.
This represents a 2.8% rate of inflation between 2015 and 2016. This is calculated by finding the percentage change in the index number over that period.

1Microeconomics

1.1Competitive Markets: Demand & Suply

1.1.1Markets & Demand

1.1.2Diminishing Marginal Returns

1.1.3Supply

1.1.4Market Equilibrium

1.1.5Price Mechanism

1.1.6Consumer & Producer Surplus

1.1.7IB Multiple Choice - Demand

1.1.8IB Multiple Choice - Supply

1.2Elasticity

1.2.1Elasticities of Demand

1.2.2Factors Affecting Price Elasticity of Demand

1.2.3Elasticity of Supply

1.2.4Price Elasticity of Supply

1.2.5IB Multiple Choice - Price Elasticity of Demand

1.2.6IB Multiple Choice - Price Elasticity of Supply

1.2.7IB Multiple Choice - Other Elasticities

1.3Government Intervention

1.3.1Indirect Taxes & Subsidies

1.3.2Application Question - Taxing Prices or Quantities

1.3.3Subsidies & Price Controls

1.3.4Deadweight Loss & Government Intervention

1.3.5Elasticity & Tax Incidence

1.3.6IB Multiple Choice - Government Intervention

1.4Market Failure

1.4.1Types of Market Failure

1.4.2Introduction to Externalities

1.4.3Negative Externalities

1.4.4Policy for Negative Externalities

1.4.5Positive Externalities

1.4.6The Deadweight Welfare Loss of Externalities

1.4.7Case Study - The Externalities of Education

1.4.8Public Goods & the Free-Rider Problem

1.4.9Asymmetric Information

1.4.10End of Topic Test - Market Failure

1.4.11Application Questions - Market Failure

1.5HL: Theory of the Firm & Market Structures

1.5.1Theory of the Firm & Market Structures

2Macroeconomics

2.1The Level of Overall Economic Activity

2.1.1The Circular Flow of Income

2.1.2Defining GDP

2.1.3Limitations of GDP

2.1.4IB Multiple Choice - Economic Indicators

2.1.5Business Cycles

2.1.6Output Gaps

2.2Aggregate Demand & Aggregate Supply

2.2.1The Aggregate Demand Curve

2.2.2Components of Aggregate Demand

2.2.3Shape of the Aggregate Demand Curve

2.2.4Shifts in Aggregate Demand

2.2.5IB Multiple Choice - Aggregate Demand

2.2.6Short & Long-Run Aggregate Supply

2.2.7Alternative Models of LRAS

2.2.8Equilibrium in the AD-AS Model

2.2.9Output Gaps & the AD-AS Model

2.3Macroeconomic Objectives

2.3.1Introduction to Unemployment

2.3.2Limitations of Unemployment

2.3.3Types of Unemployment

2.3.4Causes & Impact of Unemployment

2.3.5Defining Inflation

2.3.6Measuring Inflation

2.3.7Use of Index Numbers

2.3.8The Consumer Price Index

2.3.9Consequences of Inflation

2.3.10Causes of Inflation

2.3.11Inflation & Unemployment Tradeoff

2.3.12The Short-Run Phillips Curve

2.3.13The Long-Run Phillips Curve

2.4Economic Growth, Poverty & Inequality

2.4.1Measuring Economic Growth

2.4.2Determinants of Productivity

2.4.3Economic Growth & Productivity

2.4.4Absolute & Relative Poverty

2.4.5Inequality

2.4.6Inequality 2

2.4.7Lorenz Curve

2.4.8Government Policy on Poverty

2.4.9End of Topic Test - Poverty & Inequality

2.4.10Application - Inequality & Poverty

2.5Fiscal Policy

2.5.1Introduction to Fiscal Policy

2.5.2Fiscal Policy and AD-AS Model

2.5.3Fiscal Policy Lags

2.5.4Automatic Stabilizers

2.5.5IB Multiple Choice - Fiscal Policy

2.6Monetary Policy

2.6.1Objectives of Monetary Policy

2.6.2Monetary Policy Implementation

2.6.3Monetary Policy & AD-AS Model

2.6.4Monetary Policy Lags & Pitfalls

2.7Supply-Side Policies

2.7.1Supply-Side Policies

2.7.2Supply-Side Policies 2

3The Global Economy

3.1International Trade

3.1.1Globalisation

3.1.2Globalisation for LEDCs

3.1.3Globalisation for MEDCs

3.1.4Comparative Advantage & Trade

3.1.5Protectionism

3.1.6Arguments for Protectionism

3.1.7Arguments Against Protectionism

3.1.8End of Topic Test - Globalisation & Trade

3.1.9Case Study - Globalisation & Trade

3.2Exchange Rates

3.2.1Floating Exchange Rates

3.2.2Fixed Exchange Rate

3.2.3Effect of a Stronger & Weaker Dollar

3.3The Balance of Payments

3.3.1Balance of Payments

3.3.2Balance of Payments 2

3.3.3FDI & Reducing a BoP Deficit

3.4Economic Integration

3.4.1Customs Unions & WTO

3.4.2Merged Currency

3.5Terms of Trade

3.5.1Absolute & Comparative Advantage

3.5.2Gains from Trade

3.5.3Terms of Trade

3.5.4IB Multiple Choice - Comparative Advantage & Trade

3.6Economic Development

3.6.1Factors Influencing Growth & Development

3.6.2International Institutions

3.6.3Measures of Development

3.6.4Barriers to Development

3.6.5Case Study - The Bottom Billion

3.6.6End of Topic Test - Emerging & Developing

3.7The Role of Domestic & International Factors

3.7.1Interventionist Strategies

3.7.2Development Strategies

3.7.3Development Promotion Policies

3.7.4End of Topic Test - Growth & Global Development

3.7.5Application Questions -Growth & Global Development

3.8The Role of International Trade

3.8.1International Institutions

3.8.2End of Topic Test - Globalisation & Trade

3.9The Role of Foreign Aid

3.9.1Aid

3.9.2Limitations of Aid

3.9.3Support for Aid

3.9.4Application Questions - Developing Countries

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