Indicator Al shows the level of attainment, i.e. the percentage of a population that has successfully completed a given level of education and the relationship between level of attainment and the acquisition of basic skills. Graduation rates in Indicators A2 and A3 measure the estimated percentage of younger adults who are expected to graduate from a particular level of education during their lifetimes. Completion rates from upper secondary programmes in Indicator A2 estimate the proportion of students who enter a programme and complete it successfully within a certain period of time.