Students start diversifying their pathways significantly from age 18, although the age of transition between upper secondary and tertiary education varies substantially among countries. While at least 90% of 18-year-olds are still enrolled in upper secondary in Finland, Norway, Poland, Slovenia and Sweden, more than 60% of students in Korea and the Russian Federation are already starting their tertiary education at that age. On average across OECD countries, 26% of 19-year-olds are still enrolled in secondary education.