HD.HCI.HLOSCC BY-4.0Harmonized Test ScoresHarmonized test scores from major international student achievement testing programs.They are measured in TIMMS-equivalent units, where 300 is minimal attainment and 625 is advanced attainment. Most recent estimates are used. Year of most recent estimate shown in data notes. Test scores from the following testing programs are included: • TIMSS/PIRLS: Refers to average of test scores from TIMSS (Trends in International Maths and Science Study) and PIRLS (Progress in International Reading Literacy Study), both carried out by the International Association for the Evaluation of Educational Achievement. Data from each PIRLS round is moved to the year of the nearest TIMSS round and averaged with the TIMSS data. • PISA: Refers to test scores from Programme for International Student Assessment • PISA+TIMSS/PIRLS: Refers to the average of these programs for countries and years where both are available • SACMEQ: Refers to test scores from Southern and Eastern Africa Consortium for Monitoring Educational Quality • PASEC: Refers to test scores from Program of Analysis of Education Systems • LLECE: Refers to test scores from Latin American Laboratory for Assessment of the Quality of Education • PILNA: Refers to test scores from Pacific Islands Literacy and Numeracy Assessment • EGRA: Refers to test scores from nationally-representative Early Grade Reading Assessments • EGRANR: Refers to test scores from non-nationally-representative Early Grade Reading AssessmentsPatrinos and Angrist (2018). http://documents.worldbank.org/curated/en/390321538076747773/Global-Dataset-on-Education-Quality-A-Review-and-Update-2000-2017https://datacatalog.worldbank.org/public-licenses#cc-by HD.HCI.EYRSCC BY-4.0Expected Years of SchoolExpected years of school is calculated as the sum of age-specific enrollment rates between ages 4 and 17. Age-specific enrollment rates are approximated using school enrollment rates at different levels: pre-primary enrollment rates approximate the age-specific enrolment rates for 4 and 5 year-olds; the primary rate approximates for 6-11 year-olds; the lower-secondary rate approximates for 12-14 year-olds; and the upper-secondary approximates for 15-17 year-olds. Most recent estimates are used. Year of most recent primary enrollment rate used is shown in data notes.World Bank staff estimates based on data from UNESCO Institute for Statistics, supplemented with data provided by World Bank staff.https://datacatalog.worldbank.org/public-licenses#cc-by HD.HCI.LAYSCC BY-4.0Learning-Adjusted Years of SchoolLearning-adjusted years of school are calculated by multiplying the estimates of expected years of school by the ratio of most recent harmonized test scores to 625.World Bank staff calculation based on methodology in Filmer et al. (2018). http://documents.worldbank.org/curated/en/243261538075151093/Learning-Adjusted-Years-of-Schooling-LAYS-Defining-A-New-Macro-Measure-of-Educationhttps://datacatalog.worldbank.org/public-licenses#cc-by