Shared prosperity is one of the World Bank Group’s Twin Goals, introduced in 2013. Progress toward this goal is monitored through an indicator that measures the annualized growth rate in average household per capita income or consumption among the poorest 40 percent of the population in each country (the bottom 40), where the bottom 40 are determined by their rank in household per capita income or consumption. Chapter 2 of the 2018 Poverty & Shared Prosperity Report provides an update on the recent mixed progress on shared prosperity around the world in about 2010-15.
The shared prosperity indicator was proposed as a means to shine a constant light on the poorest segments of the population in every country, irrespective of their level of development. Shared prosperity has no target or finish line, because the aim is to continuously improve well-being. In good times and in bad, in low and high-income economies alike, the bottom 40 percent of the population in each nation would be monitored. Tracking the bottom 40’s absolute growth as well as their growth relative to the mean is a way to remind us to always consider distributional impacts and strive for equitable outcomes.
An important but challenging goal to monitor
Despite its importance and universal relevance, shared prosperity is more challenging to monitor than global poverty. While one household survey is sufficient to calculate poverty, shared prosperity measurement requires two recent comparable surveys.
The implication of this stronger data requirement is that 91 out of the 164 economies with an international poverty rate measured in PovcalNet are included in the 6th edition of the Global Database of Shared Prosperity (GDSP).