Have you ever wondered that no matter of the country of residence and level of education, women are paid 13-23 per cent less than men.
Incomes Data Services  based on publicly-available statistical data from Eurostat, the International Labour Organization and the Foundation's website WageIndicator  conducted a research in difference between wages in 63 countries, 30 of them – European countries.
Here's a summary of the study:

• The average difference in wages between men and women around the world is 15.6 per cent. In Europe, Oceania and Latin America it is slightly less than in Asia and Africa. About the situation in Asia and Africa, less information is available.
• Data from questionnaires on wages of the site WageIndicator, that asked nearly 400 000 people, showed that the difference in salary survey participants ranged from 13 to 23 percent.
• According to the study, level of education of women is the same as men or even higher. However, whether a woman of higher education does not necessarily lead to a decrease in the gap in wages. Nevertheless, the study showed that the level of female education still affects this difference.
• The gap in salaries for men and women is traditionally higher in occupations that are considered "female" - the sphere of health, education, social. While in the traditionally male-dominated professions, this difference is smaller.
• Especially significant differences were observed in sectors such as mining, service industries and financial sector.
• Public administration, social activities and the provision of personal services, show the smallest difference in wages between men and women.
• According to the Foundation WageIndicator for workers who belong to unions, the difference is less.

Source: http://www.mojazarplata.com/main/skolko-zarabatyvaet-zhenschina/raznica-v-zarplate-doc