Despite 191 countries ratifying the Convention, the births of millions of children worldwide go unregistered. By their very nature, data concerning unregistered children are approximate. About 29% of countries don't have available or sufficient data to assess global progress towards the SDG goal of universal coverage. However, from the data that is available, UNICEF estimates that more than a quarter of children under 5 worldwide are unregistered. The lowest levels of birth registration are found in sub-Saharan Africa (43 percent). This phenomenon disproportionately impacts poor households and indigenous populations. Even in many developed countries, it contributes to difficulties in fully accessing civic rights.