It should be noted that gender inequality can also be used to denote a situation where men are disadvantaged vis-a-vis women (as nowadays can be observed in some countries in the case of certain measures of educational attainment or of health status); however, as this is historically almost never the direction in which the inequality runs, the bulk of this chapter looks at how gaps disadvantageous to women have been closed over the past century. This is also to address an imbalance in the rest of the book by which almost all the other chapters either are focused on men or provide no data on indicators disaggregated by gender. Others include the Gender Empowerment Index by the UNDP, the Social Institutions and Gender Index by the OECD, the Global Gender Gap Index by the World Economic Forum and the Women’s Economic Opportunity Index produced by the Economist Intelligence Unit. The UN uses a correction of five years because there is some evidence to show that at a biological level women have a greater life expectancy.