Many of the measures on quantifying progress by countries towards reducing income inequality have focused on indices that measure trends in inequality over time (Gini coefficient for example) and compare countries without considering the differences between their socioeconomic structures.

However, these indices do not paint the complete picture about how countries are performing, especially when compared to one other in achieving Sustainable Development Goals and what policies and investments may be needed to support them. This research project will provide an alternative measurement of income inequality by taking into account the developing countries’ structural or predetermined conditions (mineral assets, type of institutions etc.) in assessing their progress towards reducing inequality and the impacts of climate change. 

The project focuses on the following objectives: 

1. Firstly, it will compare each country with its potential to reduce income inequalities by measuring the scope for improvement for each country at every year. This will allow a better understanding of the key factors that hinder a country’s effort and performance in reducing inequalities and of the policy and investments that are needed to tackle inequalities more efficiently.
2. Secondly, it will investigate how climate – temperature, precipitation and extreme weather events– influence the efficiency of countries in combining inputs to reduce inequality.
3. Thirdly, it will look at adaptation or intensification effects across regions, particularly in LDCs and SIDS and will identify the needed scale of investments.

Building on a panel database on 145 countries, including countries from Least Developed Countries (LDCs) and Small Island Developing States (SIDS) from 2000-2020, the project will use a stochastic frontier approach, an economic modelling technique, to estimate feasible frontiers for income inequality for each country and year.

You will find below the research paper related to this project:

• Reducing Inequalities Despite Climate change? Rethinking Progress Towards Reducing Income Inequalities and the Impact of Climate Change in Developing Countries

This research project proposes to estimate the distributive effect of gasoline taxes using a fiscal incidence considering these effects in the context of Mexico´s fiscal system, including the principal tax and spending instruments. 

In 2014, Mexico’s Finance Ministry (SHCP) introduced a special tax (IEPS) on carbon as a green tax aimed at reducing the green gas emission associated with fossil fuels, mainly gasoline and diesel. However, the tax revenue (4699 million pesos in 2014) and the environmental impact of this tax are marginal: in the past decade, until 2014, this tax had a negative value, thus working as a subsidy. Since that year, it became a tax, which has grown significantly in recent years, representing close to 300 billion pesos in 2019 and 2020. This is therefore in effect by far the most important green tax implemented in Mexico today. 

This analysis is of particular interest for Mexico at present because the transition from fuel subsidies to fuel taxes represents in effect the principal tax reform implemented in Mexico over the last decade in terms of both tax revenue (from -300 to +300 billion pesos in tax revenue) and distribution. Gasoline taxes have significant impacts on all the population, both directly on middle- and higher-income households through private transport, but especially indirectly for lower income households through public transport and transport costs for all goods and services, notably food. Preliminary analysis at the Fiscal Policy Equity Lab (FPEL) reveals that the increase in the indirect tax burden for the poor associated to gasoline taxes may reverse the effect poverty-reduction effect of direct transfers, even after their recent expansion. 

Quantifying these impacts precisely will allow the design of compensatory instruments to protect the poorest and most vulnerable groups from the regressive effects of these taxes. 

Find out more about the Extension in Mexico

This project is a joint undertaking between RIBOS, CEQ Institute and LNPP. It seeks to estimate the effect of green taxes in the context of the overall Mexican tax system through the international methodology developed by the Commitment to Equity Institute (CEQI), using INEGI data from the Encuesta de Ingresos y Gastos de los Hogares (ENIGH) for 2014-2020, among other data sources. 

This methodology will allow an estimation the effect of green taxes in the context of the overall fiscal system. This methodology facilitates comparability in time and space, and generates a wide variety of incidence indicators, including effects on the income Gini coefficient as well as income poverty using national and international poverty lines. 

This project ultimately aims to provide Mexican policy makers and stakeholders with timely analyses of the effects of tax policies on inequality and poverty. The research conducted will therefore result in: 

• a research paper,
• a policy brief whose analysis is based on the collaborative intelligence technique. Two sessions in which the model calibration and hypotheses will be discussed following the collaborative modeling framework. Participants in the sessions will be members of the expert network and key tax policy makers.

You will find below the research paper related to this project:

• Distributive impact of green taxes in Mexico (July 2024)

The policy brief related to this project will be published here soon.