The United States has the lowest percentage of residents considered middle-class, the largest difference in P90/P10, and is ranked last in child income poverty, income inequality after taxes, and index of health and social problems.

INCOME DISTRIBUTION

COLOR CODING
GreenRanked first for statistic
RedRanked last for statistic
 GINI IndexYearSize of Middle class %Poverty rate with poverty line at 50%P90/P10Percent of population below poverty lineYearIncome inequality after taxes rankingMulti-dimensional Poverty IndexIncome Inequality: Quintile Index
Australia35.820140.124.3105.8
Canada34.020130.124.19.4200886.2
Denmark28.22015800.062.913.4201140.0204.0
France32.72015740.083.414.2201570.0355.2
Germany31.72015720.103.816.7201550.0305.1
Italy35.42015670.144.529.9201290.0636.6
Japan32.120080.165.216.1201315.4
Netherlands28.22015790.083.48.8201560.0214.4
Norway27.52015800.083.120.0124.1
Sweden29.220150.093.315.0201430.0214.6
United Kingdom33.22015670.114.215.02013110.0285.4
United States41.52016590.186.315.12010129.4

SOURCES

GINI index: World Bank (estimate)

“Gini index measures the extent to which the distribution of income (or, in some cases, consumption expenditure) among individuals or households within an economy deviates from a perfectly equal distribution. A Lorenz curve plots the cumulative percentages of total income received against the cumulative number of recipients, starting with the poorest individual or household. The Gini index measures the area between the Lorenz curve and a hypothetical line of absolute equality, expressed as a percentage of the maximum area under the line. Thus a Gini index of 0 represents perfect equality, while an index of 100 implies perfect inequality.”
“Data are based on primary household survey data obtained from government statistical agencies and World Bank country departments.”
*as of 2015 the World of Work Report has been replaced by a new annual ILO flagship series, the World Employment and Social Outlook (WESO)

Size of Middle Class Percent: Pew Research Center

“In this report, “middle-income” adults have annual disposable household incomes from two-thirds to double the national median disposable household income, after incomes have been adjusted for household size.”
Percent of adults living in middle-income households in 2010. Data for Western European countries and United States.

Poverty rate with poverty line at 50%: OECD

OECD: Social Protection and Well-being > Income Distribution and Poverty
Poverty rate after taxes and transfers (using new 2012 income definition). All data from 2016 except Denmark and Japan (2015).

P90/P10: OECD

Social Protection and Well-being > Income Distribution and Poverty
The P90/P10 ratio is the ratio of the upper bound value of the ninth decile (i.e. the 10% of people with highest income) to that of the upper bound value of the first decile.
All data from 2016 except Canada, Denmark and Japan (2015).

Percent of population below the poverty line: CIA World Factbook

*Definitions of poverty vary among nations, poverty line is drawn differently for each country.

Multidimensional Poverty Index: Oxford Poverty & Human Development Initiative, 2012

Values for 2012 for European countries.

Income Inequality: Quintile Ratio

The quintile ratio compares the top 20% with the bottom 20%, a smaller number indicates a small difference between the two.

NOTES

Paid family leave in the United States

Updated May 29, 2019
Congressional Research Service

“Fewer millennials are making it into the middle class”

Tami Luhby, April 11, 2019
CNN Business. The middle-class is not just shrinking in the U.S. but also in other developed countries, according to a report by the OECD. Millennials are finding it increasingly difficult to achieve middle-class status compared to previous generations.
“The share of people in middle-income households in developed countries fell from 64% in the mid-1980s to only 61% by the mid-2010s. However the declines were larger in several countries, including the United States, Israel, Germany, Canada, Finland and Sweden.”