Life expectancy is defined as the average number of years that a person could expect to live if he or she experienced the age-specific mortality rates prevalent in a given country in a particular year. It does not include the effect of any future decline in age-specific mortality rates. Each country calculates its life expectancy according to somewhat varying methodologies. These methodological differences can affect the exact comparability of reported estimates, as different methods can change a country’s measure of life expectancy slightly. Life expectancy data was from 2008 except the following: Belgium, Canada, Italy, the United Kingdom and the United States all 2007. Chile, France, Mexico, the Netherlands and Sweden all 2009. Life expectancy changes are calculated from 1983 to 2008, except for those countries where the latest figure is 2007, in which case this is used. Household income and income inequality data are discussed in GE1 and EQ1. The Gini coefficient is a measure of income inequality. Values range between 0 – perfect equality – and 1 – all income goes to one person.