The rate of early school leavers is defined as the proportion of the population aged 18-24 with only lower secondary education or less and no longer in education or training.
Haridussüsteemist varakult lahkunute osakaal väljendab seda, kui suur osa 18–24aastastest elanikest on vaid teise taseme alumise astme või sellest madalama taseme haridusega ning ei osale enam hariduses ega koolituses.