Significant disparities in access to social services within countries are also stratified by area of residence and by gender. Many economies in the region have failed to raise sufficient tax revenue despite rapid growth, as demonstrated by their low and stagnant tax-to-GDP ratios (see figure 1.21). The stagnant tax-to-GDP ratios when the economy was growing indicate lack of sufficient progressivity of the tax structure. Declines in formal employment and the consequent rise in vulnerable employment are also contributing to the growing inequality through the falling share of wages in GDP. There is a clear negative relationship between the tax burden of countries in the region and their levels of inequality (see figure 1.22).