But if you are interested in unemployment rates, and not in the number of unemployed people, it does not matter. For example, both Spain and Italy have higher p

But if you are interested in unemployment rates, and not in the number of unemployed people, it does not matter. For example, both Spain and Italy have higher population density in their North regions, but a map that was somewhat normalized with respect to population density would not be clearer to show the fact that unemployment rates are much higher in Sevilla than San Sebastian, or in Lecce than in Milan. Of course, if you assume that you can derive the number of unemployed people using an average population density (ie. that the size of the regions is proportional to population), the map will not work. But in that case the problem would not be the map but a wrong assumption. A map is not a histogram.