Income inequality measurement sensitivities /

The income shares for the top 10 percent of individuals in 2010 vary from a low of 30.0 percent (for after-tax income) to a high of 41.7 percent (for earnings)—a 39.0 per- cent increase in the level of income inequality entirely due to the choice of definition. [...] To the extent that the information collected by the survey is accurate, the quintile distribution presented in table 1 illustrates income inequality in Canada.4 Based on reported incomes, the top 20 percent of families in 2010 had 47.1 percent of the total income whereas the bottom 20 percent had 4.2 percent of total income. [...] Recent work, particularly Piketty’s Capital in the 21st Century relies on a variant of the decile/quintile share ratios: the top decile share of income.5 Rather than measure the ratio of the top 10 percent and the bottom 10 per- cent, the decile share measures the share of income received by the top 10 percent of individuals or families. [...] The Lorenz curve represents the actual distribution of income; the further away the curve is from the line of equality, the less equal the distribution. [...] The reality is that the income of the working partner is shared by the entire family, which means the appropriate recipient unit is the family.