The average age of teachers is 48.1 years in primary education and 48.9 in secondary' education. Some 41% of primary teachers and 44% of lower secondary teachers were 50 years old or older in 2014, which are significantly higher than the OECD averages (30% and 34%, respectively). The cognitive skills of the teaching workforce are a significant determinant of international differences in student performance (Hanushek, Piopiunik and Wiederhold, 2016).