Number of pupils and apprentices, 25 years or older, who started in upper secondary education five years ago. Everybody who is 25 years or older is counted as an adult and starting time is calculated independent of level of education. To limit the content for "new" adult participants, the claim is that they will not have activity three years before starting time. The starting population does not include candidates for experience-based trade verification. Source: National Education Database (NUDB).