The gap is based on the difference in gross hourly earnings between men and women, and ranges from just 4.9 per cent in Italy to 30 per cent in Estonia. [Source.]The average gap across countries is 18 percent. But what is this number based on? On the "difference in gross hourly earnings between men and women", as it says. I am just not sure what that means. How is it calculated?
Is it the difference in hourly wage per person, or is it a comparison of what all women and men earn in Europe per hour? If it is per person, then it sounds really bad. If it is not per person, then it could readily be explained by more men than women earning a salary. I don't know if that would be true, but it seems a fair guess. Either way, the number should be per person earning a salary, in order to make the comparison valid.
But, even if the comparison is per person, then it would also have to be corrected for what kind of jobs European men and women have. It may well be that more men have higher paying jobs, as in more men are physicians, and more women are nurses, or some such distribution. If that's the case, that more women for some reason or other are in the kind of jobs that just generally pay less per hour, then the gap is not unfair. On the other hand, if the comparison is made across all nurses, and it turns out that male nurses earn more than female nurses per hour, then something is indeed very, very wrong, and something ought to be done right away.
Until I know how the gap is calculated (I have looked and cannot find that description - do let me know if you find any documentation on this), I don't feel so sure that taking measures to reduce the gap is the right thing to do.
Gender pay gap across Europe condemned
Pledge to cut EU gender pay gap after 15 years without progress
Danske mænd tjener 18 procent mere end kvinder
EU to propose hiking women's pay
UK women get 21% less than men
Oh, and a related post from last year about the meaning of averages.