**1. Introduction**

This study analyzes inequality affecting the 63 million Mexican women (or 50.1% of the total population) in the three Mexican population groups. The focus of the analysis is to measure women's inequality across all Mexican Societies and in the three and main population groups that conform to it according to the 2020 Population Census. The main interest is put in the discrimination of all women vis a vis men in total population and in each group and less on the characteristics of women discrimination in each. The intention is to reflect on and analyze the causes and consequences of the horizontal inequalities faced by women rather than to analyze them as an effect of the intersectionality of gender and ethnicity. In a strict sense, it is not an intersectionality analysis although some aspects of interferences are discussed all along with the text. Both HI and interdisciplinary analysis overlap in important aspects and differs in others. Both start from multidimensional approaches, but while the former concentrates on dimensional intersectionality focusing on a global analysis of inequalities between groups as a whole, the latter concentrates on the analysis of those categories which are particularly deprived because of intersectionality [1].

In this study the focal analysis is on the discrimination exercised against women in society, which is reinforced with elements of intersectionality, it is discrimination that is reproduced within each population group. In a country as culturally diverse as Mexico, we consider it relevant to approach gender discrimination in society and the country's ethnic groups, two of them, the Indigenous and Afro-descendant population, objects of discrimination; this analysis has not been sufficiently studied from the perspective of HI [1] and in Mexico, partly because of the difficulties in identifying ethnic groups in the statistics.<sup>1</sup>

Therefore, based on the HI approach, this study analyzes gender discrimination against women in the Indigenous and Afro-descendant populations and for those who do not self-identify as belonging to any of these ethnic groups. It shows the perpetuation of discrimination by the interplay between Mexico's original cultures and the formal and informal institutions brought by the conquerors, maintained and reinforced in the colonial era, and again in the political constitutions of the Latin American republics that gave the vote only to literate men and landowners. The right to vote was not extended to women until well into the twentieth century, later than to Indigenous and Afro-descendant men.

Horizontal inequality, or inequality between social groups that differ in ways such as ethnicity, culture, religion, or gender, is at the root of gender, ethnic, tribal and minority claims, fundamental rights contained in various United Nations agreements,<sup>2</sup> establishing minimum thresholds of equity in necessary goods but allowing a certain inequality in non-essential goods and goods distributed by merit. Horizontal inequality can be used to identify the areas and factors in which these gaps in rights and inequalities prevail between men and women.

Understanding the gender discrimination that affects more than half of the world's population requires accepting the intensity and variety of the factors that determine and perpetuate it. Measuring the inequality experienced by Mexican women implies recognizing both, the breadth and depth of the social gaps existing in the country, the social debt they imply and the profundity of discrimination that often passes for normal or idiosyncratic behavior.

A quantitative exploration was required to measure these gender gaps, so a Gender Equality Index is constructed, which allows estimating gender gaps in various factors and grouping them for each area of HI. An index is then provided for each area of HI to obtain an aggregate index as a global reference for gender inequality and from which it is possible to compare gender inequality between population groups. For so doing the *Censo de Población y Vivienda 2020* (Census of Population and Housing 2020) was used. The Censo is the statistical source in

<sup>1</sup> The identification of Indigenous people by language began with the 1990 population census; it was not until 2015 that Afro-descendants were identified.

<sup>2</sup> These agreements are the Universal Declaration of Human Rights, the International Covenant on Economic, Social and Cultural Rights and on Civil and Political Rights (1966); the Convention on the Elimination of All Forms of Discrimination Against Women (1979); Declaration on the Right to Development (the fourth contains the recommendations); the Convention on the Rights of the Child (1986) and the 2007 United Nations Declaration on Indigenous Peoples.

Mexico that provides the latest official count of inhabitants in Mexico. It allows identifying the three main population conglomerates: the Indigenous population, the Afro-descendant population and all others.
