Missing women describes the difference between the number of women that should be alive (assuming gender equality) and the actual number of women in a country. Among other things, reasons for "missing women" include sex selective abortions due to son-perferences. A value of 1 was assigned to the country with the highest percentage of missing women relative to the total number of women (i.e. Afghanistan with a share of 9.3 percent). All other countries are assigned values between 0 (no women are missing) and 1 accordingly.

Based on Sen, A.: More than 100 Million Women are Missing, The New York Review of Books (2000) and Klasen, S. and C. Wink (2003): Missing Women: Revisiting the Debate, Feminist Economist, 9(2-3), pp. 263-299.