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Average years of schooling

UNDP
See all data and research on:
Human Development Index (HDI)

What you should know about this indicator

  • Mean years of schooling shows the average number of years that adults in a country have spent in formal education, reflecting the overall educational attainment of the population.
  • It is calculated based on the highest level of education completed, converted into years—e.g. someone who finished high school is counted as having roughly 12 years of schooling.
  • The data comes from censuses and surveys of adults aged 25 and older, and includes only formal education starting from primary school.
  • This indicator captures how much schooling adults have accumulated over their lifetimes, highlighting the results of past investments in education systems.
  • Higher values suggest a population with stronger educational foundations. However, the measure does not account for education quality, informal learning, or improvements among younger generations who may be better educated than older adults.
  • In countries with infrequent surveys or outdated census data, the values may not reflect recent progress or changes in educational access.
  • UNDP originally obtained this indicator from: Barro and Lee (2018), Eurostat (2024), ICF Macro Demographic and Health Surveys (various years), UNESCO Institute for Statistics (2024) and UNICEF Multiple Indicator Cluster Surveys (various years).
Average years of schooling
UNDP
Average number of years (excluding years spent repeating individual grades) adults over 25 years participated in formal education.
Source
UNDP, Human Development Report (2025) – with minor processing by Our World in Data
Last updated
May 7, 2025
Next expected update
May 2026
Date range
1990–2023
Unit
years

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Sources and processing

This data is based on the following sources

Artificial intelligence (AI) has broken into a dizzying gallop. While AI feats grab headlines, they privilege technology in a make-believe vacuum, obscuring what really matters: people's choices.

The choices that people have and can realize, within ever expanding freedoms, are essential to human development, whose goal is for people to live lives they value and have reason to value. A world with AI is flush with choices the exercise of which is both a matter of human development and a means to advance it.

Going forward, development depends less on what AI can do—not on how human-like it is perceived to be—and more on mobilizing people's imaginations to reshape economies and societies to make the most of it. Instead of trying vainly to predict what will happen, the 2025's Human Development Report asks what choices can be made so that new development pathways for all countries dot the horizon, helping everyone have a shot at thriving in a world with AI.

For more details, refer to https://hdr.undp.org/data-center/documentation-and-downloads

Retrieved on
May 7, 2025
Retrieved from
https://hdr.undp.org/
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.
UNDP (United Nations Development Programme). 2025. Human Development Report 2025: A matter of choice: People and possibilities in the age of AI. New York.

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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.

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  • 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: Average years of schooling”, part of the following publication: Bastian Herre and Pablo Arriagada (2023) - “The Human Development Index and related indices: what they are and what we can learn from them”. Data adapted from UNDP, Human Development Report. Retrieved from https://ourworldindata.org/grapher/average-years-of-schooling [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:

UNDP, Human Development Report (2025) – with minor processing by Our World in Data

Full citation

UNDP, Human Development Report (2025) – with minor processing by Our World in Data. “Average years of schooling – UNDP” [dataset]. UNDP, Human Development Report, “Human Development Report” [original data]. Retrieved June 16, 2025 from https://ourworldindata.org/grapher/average-years-of-schooling