The Spirit Level: Why Greater Equality Makes Societies Stronger Read Online Free PDF Page A

or 25 per cent of all incomes and the richest half get the remaining 75 or 80 per cent. Other more sophisticated measures include one called the Gini coefficient. It measures inequality across the whole society rather than simply comparing the extremes. If all income went to one person (maximum inequality) and everyone else got nothing, the Gini coefficient would be equal to 1. If income was shared equally and everyone got exactly the same (perfect equality), the Gini would equal 0. The lower its value, the more equal a society is. The most common values tend to be between 0.3 and 0.5. Another measure of inequality is called the Robin Hood Index because it tells you what proportion of a society’s income would have to be taken from the rich and given to the poor to get complete equality.
    To avoid being accused of picking and choosing our measures, our approach in this book has been to take measures provided by official agencies rather than calculating our own. We use the ratio of the income received by the top to the bottom 20 per cent whenever we are comparing inequality in different countries: it is easy to understand and it is one of the measures provided ready-made by the United Nations. When comparing inequality in US states, we use the Gini coefficient: it is the most common measure, it is favoured by economists and it is available from the US Census Bureau. In many academic research papers we and others have used two different inequality measures in order to show that the choice of measures rarely has a significant effect on results.
    DOES THE AMOUNT OF INEQUALITY MAKE A DIFFERENCE?

    Having got to the end of what economic growth can do for the quality of life and facing the problems of environmental damage, what difference do the inequalities shown in Figure 2.1 make?
    It has been known for some years that poor health and violence are more common in more unequal societies. However, in the course of our research we became aware that almost all problems which are more common at the bottom of the social ladder are more common in more unequal societies. It is not just ill-health and violence, but also, as we will show in later chapters, a host of other social problems. Almost all of them contribute to the widespread concern that modern societies are, despite their affluence, social failures.
    To see whether these problems were more common in more unequal countries, we collected internationally comparable data on health and as many social problems as we could find reliable figures for. The list we ended up with included:
• level of trust
• mental illness (including drug and alcohol addiction)
• life expectancy and infant mortality
• obesity
• children’s educational performance
• teenage births
• homicides
• imprisonment rates
• social mobility (not available for US states)
    Occasionally what appear to be relationships between different things may arise spuriously or by chance. In order to be confident that our findings were sound we also collected data for the same health and social problems – or as near as we could get to the same – for each of the fifty states of the USA. This allowed us to check whether or not problems were consistently related to inequality in these two independent settings. As Lyndon Johnson said, ‘America is not merely a nation, but a nation of nations.’
    To present the overall picture, we have combined all the health and social problem data for each country, and separately for each US state, to form an Index of Health and Social Problems for each country and US state. Each item in the indexes carries the same weight – so, for example, the score for mental health has as much influence on a society’s overall score as the homicide rate or the teenage birth rate. The result is an index showing how common all these health and social problems are in each country and each US state. Things such as life expectancy are reverse scored, so that on every measure higher scores