A methodological note on the global Multidimensional Poverty Index (MPI) 2023 changes over time results for 84 countries

This Methodological Note presents the methodology and policies that underlie the harmonised level estimates and their changes over time in multidimensional poverty for 84 countries. 35 of the 84 countries have trends for three points in time; while poverty trends in 45 countries are based on two points in time. Four countries, Gambia, Mexico, Nigeria and Peru, have results for four points in time. We also estimate how multidimensional poverty changed by four major age categories (0 to 9 years, 10 to 17 years, 18 to 59 years, and over 60 years) and by two age categories covering children aged 0 to 17 years and adults 18 years and older in all countries. Our results also show poverty trends by rural-urban area and by 814 subnational regions. We standardised and harmonised 211 survey datasets to estimate the harmonised levels and changes in multidimensional poverty. Indicator standardisation is detailed in Alkire, Kanagaratnam and Suppa (2023a). This document, focused on harmonisation methodology and principles, is structured as follows. Section 2 presents the global MPI structure and indicator definitions. Section 3 provides an outline of the global MPI and its partial indices that we estimate and publish. Section 4 summarises the changes over time methodology. Section 5 provides a summary of the harmonised surveys. Section 6 outlines the principles and decisions that underlie our harmonisation work. Section 7 summarises the country-specific decisions that were applied for the datasets harmonised in this round. We conclude with brief reflections.