Affirmative actions should be understood as targeted temporary actions aiming to facilitate access, participation, and completion of marginalised groups that are underrepresented in different levels of education.
Total primary (or secondary) school age children who are not enrolled (because they never enrolled or because they dropped-out) in primary or secondary education expressed as a percentage of the official school-age population corresponding to the primary (or secondary) level in a given school-year. Children enrolled in pre-primary education are excluded and considered out-of-school (Source: UIS)
GER is the ratio of total enrolment, regardless of age, to the population of the age group that corresponds to the same level of education. GER can exceed 100% due to the inclusion of over-aged and under-aged students, because of early or late school entrance, and grade repetition. For the tertiary level, the population used is the 5-year age group starting from the official secondary school graduation age (Source: UIS, Education Indicators - Technical Guidelines: p.9)
Marginalised groups are all those excluded from governmental policy and access to education including: women and girls, indigenous peoples and minorities, persons with disabilities, persons with HIV / AIDS, child labourers, persons in detention, migrants, refugees and IDPs, and persons living in poverty (Source: Audrey Chapman (2007) Development of Indicators for Economic, Social and Cultural Rights: The Rights to Education, Participation in Cultural Life and Access to the Benefits of Science: p.145)
Percentage of students at the lowest level of science proficiency is the percentage of students at the lowest level of proficiency on the science scale in national or international assessments
Percentage of students at the lowest level of mathematics proficiency is the percentage of students at the lowest level of proficiency on the mathematics scale in national or international assessments
Percentage of students at the lowest level of reading proficiency is the percentage of students at the lowest level of proficiency on the reading scale in national or international assessments