They are highest in sub-Saharan Africa, where 88 per cent of children (202 million) of primary and lower secondary school age were not proficient in reading, and 84 per cent (193 million) were not proficient in mathematics in 2015. Central and Southern Asia was not faring significantly better. There, 81 per cent of children (241 million) were not proficient in reading, and 76 per cent (228 million) lacked basic mathematical skills. The next decade provides an important window of opportunity for policymakers to ensure that all children are proficient in basic literacy and numeracy.