Powered by Leeds Metropolitan University
Visit the new tutor2u website

Our new website is now in Beta-mode with a brand new collection of study notes and other resources for A Level & IB Economics. Visit the new tutor2u Economics website here.

Interpreting Economic Data

Author: Geoff Riley  Last updated: Sunday 23 September, 2012


In this revision note we will look at some of the ways that data can be presented including:

  1. Tables of data
  2. Graphs and index numbers
  3. The difference between percentages and percentage changes
  4. Distinguishing between real and nominal economic data

Tables of data

The table below shows time series data covering consumer spending over the years 2004 through to 2008.


Column 1
New car registrations

Column 2
Household saving ratio

 Column 3
Real Household Disposable Income

Column 4

Growth of consumer credit







% change
































YOY means – year on year percentage change

Column one shows the number of new car registrations and is presented in two ways. Firstly the actual number each year and secondly the year-on-year change measured as a percentage. When we want to calculate a percentage change from one year to another, we take the change in the value and divide by the original value and then multiply by one hundred.

So if we take the % change from 2007 to 2008 as an example

The change in new car registrations is -274,000 divided by the 2007 figure and then multiplied by 100 to give us a percentage change.

= (-274,000 / 2,390,000) 100 = -11.5% (to one decimal place) – a sharp fall in car sales!

Column 2 provides information on the household saving ratio. Notice here that the data is measured as the amount of saving that households are doing expressed as a percentage of disposable income. It appears that the savings ratio has fallen over the years – to less than 3% in 2007 and 2008. But be aware that:

  • Although the savings ratio has fallen, average incomes have grown so we should be cautious about saying that the total amount that people save has declined.
  • The figure is an average across the whole economy – and average values must always be treated with care because for most people, their own savings ratio will either be higher or lower than the published figure, depending on their own financial situation, how much income they have. And also what stage they have reached in their life-cycle.

Columns 3 and 4 show the annual growth of real disposable income and consumer credit – two important variables that affect how much people have available to spend on goods and services.
A quick comparison of the two data series shows that consumer credit has been rising more strongly in each of the years shown. If you are given this data in an exam it might be worth doing a rough estimate of the average growth each year for your answer.

Real disposable income rose in each of the years shown – it is important to understand the difference between a fall in the rate of growth and an actual fall. For example between 2006 and 2007 real take-home incomes rose by 0.5%; this is a slower rise than the year before but still an increase. Likewise for consumer credit, the % change each year has been positive – but in 2007 and 2008 we see a significant fall in the rate of growth – from over 12 per cent to 6 per cent.

Using Index Numbers

  • Index numbers are a useful way of expressing pieces of information and collections of data. This section shows you how to express data in index number format and some examples of data which is commonly presented as an index number.
  • In economic data, an index number is a figure reflecting price or quantity compared with a standard or base value.
  • The base value equals 100 and the index number is expressed as 100 times the ratio to the base value.

Examples of data expressed in index number format

The consumer price index is a measure of prices for hundreds of different goods and services in the UK economy. The value of the index for each category e.g. clothing and footwear is set to a value of 100 at the start of 2005. A fall in the index tells us that prices are falling (deflation) and a rise indicates higher prices (inflation). Consider the chart below


Add your comments and share this study note:

blog comments powered by Disqus


Search tutor2u

Order by 

Related study notes

Buy your personal copy of our Economics revision guides

tutor2u Economics Revision Guides

Behavioural Economics
Network Economics
Game Theory
Business Economics
Economics of Utilities
Contestable Markets
Competitive Markets
Economies of Scale
Management Issues
Monopolistic Competition
Price Discrimination
Competition Policy
Commodities Markets
Emerging Economies
Human Development
African Economy
South African Economy
Kenyan Economy
Development Economics
Brazil Economy
China Economy
Indian economy
Russia Economy
Cost Benefit Analysis
Cycles and Shocks
Aggregate Demand
Capital Investment
Consumer Spending
Aggregate Supply
Economic History
Economic Growth
Economics of Technology
Environmental Economics
European Economy
EU Enlargement
EU Farming and Fishing
Single Market
The Euro
Exchange Rates
Money and Finance
Global Economy
Balance of Payments
Credit Crunch
International Trade
Housing Economics
Government Intervention
Buffer Stocks
Government Failure
Indirect Taxes
Maximum Prices
Minimum Prices
Health Economics
Inflation and Deflation
Labour Market
Trade Unions
Introductory Economics
Macroeconomic Policies
Fiscal Policy
Monetary Policy
Supply-side policies
Trade Policies
Keynesian Economics
Market Failure
Factor Immobility
Information Failure
Merit & De-Merit Goods
Public Goods
Manufacturing Industry
Oil and Gas
OECD Economies
Australia Economy
French Economy
German Economy
Greece Economy
Ireland Economy
Japan Economy
Spain Economy
US Economy
Poverty and Inequality
Market Equilibrium and Price
Elasticity of Demand
Elasticity of Supply
Nature of Demand
Nature of Supply
Price Mechanism in Action
Price Volatility
Inter-related Markets
Standard of Living
Transport Economics
UK Economy
Regional Economics
London Economy
Recession Watch



Tutor2u support for students
Teaching support and resources
Search for resources on tutor2u

Refine Search by Subject
A Level Economics
Business Studies
Geography Give It A Go!
History Law
IB Diploma Politics
Religious Studies Sociology

Order Search Results By

Follow tutor2u on Twitter

tutor2u Home Page | Online Store | About tutor2u | Copyright Info | Your Privacy | Terms of Use


Boston House | 214 High Street | Boston Spa | West Yorkshire | LS23 6AD | Tel +44 0844 800 0085 | Fax +44 01937 529236

Company Registration Number: 04489574 | VAT Reg No 816865400