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Data

Share of the population aged 25+ years with lower secondary education

See all data and research on:
Global Education

What you should know about this indicator

  • This indicator shows what portion of the adult population (aged 25 and above) has attained at least a lower secondary level of education.
  • It is calculated by dividing the number of adults who have completed at least lower secondary education by the total population in the same age group, and multiplying by 100.
  • Lower secondary education typically corresponds to ages 12 to 15 or 16.
  • The 25+ age group is used because most people have completed their formal education by this age, making it a reliable population for tracking educational attainment.
  • The data come from national censuses, labour force surveys, or other household surveys, and are usually mapped to the International Standard Classification of Education (ISCED) after data collection.
  • There are important limitations to consider. Comparisons across countries may be affected by differences in how qualifications are mapped to ISCED levels, and some educational programmes may not be easily classified.
  • In addition, the indicator reflects only the level of education completed — not the quality of education or whether the person uses their qualification in the labour market.
Share of the population aged 25+ years with lower secondary education
Percentage of adults aged 25 and older who have completed or higher.
Source
UNESCO Institute for Statistics (2025) – with minor processing by Our World in Data
Last updated
May 1, 2025
Next expected update
May 2026
Date range
1970–2024
Unit
%

Sources and processing

This data is based on the following sources

The UNESCO Institute for Statistics (UIS) is the official and trusted source of internationally-comparable data on education, science, culture and communication. As the official statistical agency of UNESCO, the UIS produces a wide range of state-of-the-art databases to fuel the policies and investments needed to transform lives and propel the world towards its development goals. The UIS provides free access to data for all UNESCO countries and regional groupings from 1970 to the most recent year available.

Retrieved on
May 1, 2025
Retrieved from
https://databrowser.uis.unesco.org/resources/bulk
Citation
This is the citation of the original data obtained from the source, prior to any processing or adaptation by Our World in Data. To cite data downloaded from this page, please use the suggested citation given in Reuse This Work below.
UNESCO Institute for Statistics (UIS), Education, https://uis.unesco.org/bdds, 2025

How we process data at Our World in Data

All data and visualizations on Our World in Data rely on data sourced from one or several original data providers. Preparing this original data involves several processing steps. Depending on the data, this can include standardizing country names and world region definitions, converting units, calculating derived indicators such as per capita measures, as well as adding or adapting metadata such as the name or the description given to an indicator.

At the link below you can find a detailed description of the structure of our data pipeline, including links to all the code used to prepare data across Our World in Data.

Read about our data pipeline

Reuse this work

  • All data produced by third-party providers and made available by Our World in Data are subject to the license terms from the original providers. Our work would not be possible without the data providers we rely on, so we ask you to always cite them appropriately (see below). This is crucial to allow data providers to continue doing their work, enhancing, maintaining and updating valuable data.
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Citations

How to cite this page

To cite this page overall, including any descriptions, FAQs or explanations of the data authored by Our World in Data, please use the following citation:

“Data Page: Share of the population aged 25+ years with lower secondary education”, part of the following publication: Hannah Ritchie, Veronika Samborska, Natasha Ahuja, Esteban Ortiz-Ospina, and Max Roser (2023) - “Global Education”. Data adapted from UNESCO Institute for Statistics. Retrieved from https://ourworldindata.org/grapher/share-of-the-population-with-at-least-some-secondary-education [online resource]
How to cite this data

In-line citationIf you have limited space (e.g. in data visualizations), you can use this abbreviated in-line citation:

UNESCO Institute for Statistics (2025) – with minor processing by Our World in Data

Full citation

UNESCO Institute for Statistics (2025) – with minor processing by Our World in Data. “Share of the population aged 25+ years with lower secondary education” [dataset]. UNESCO Institute for Statistics, “UNESCO Institute for Statistics (UIS) - Education” [original data]. Retrieved May 18, 2025 from https://ourworldindata.org/grapher/share-of-the-population-with-at-least-some-secondary-education