Data on income difficulties is drawn from the Gallup World Poll. The Gallup World Poll is conducted in over 140 countries around the world based on a common questionnaire, translated into the predominant languages of each country. With few exceptions, all samples are probability based and nationally representative of the resident population aged 15 years and over in the entire country, including rural areas. While this ensures a high degree of comparability across countries, results may be affected by sampling and non-sampling error. Sample sizes vary between around 1 000 and 4 000, depending on the country. The Gallup data for this question does not include Switzerland. The data used is the response to the question "Which one of these phrases comes closest to your own feelings about your household’s income these days?". The following four responses are possible: Living comfortably on present income, Getting by on present income, Finding it difficult on present income, Finding it very difficult on present income. The statistics presented combines the last two categories. Rates calculated omitted don’t knows and refused from the denominator. This non-response was 11% in Italy and also high in the Russian Federation and Belgium (7%). Household income data sources are described in CO1 and income distribution data in EQ1 and EQ2. The Gini coefficient is a measure of income inequality. Values range between 0 – perfect equality – and 1 – all income goes to one person.