Girls Outscore Boys in Reading in 89 of 90 Education Systems

How the Global Math Leaderboard Has Changed

The global landscape for math achievement has shifted significantly over the past two decades.

This visualization compares Programme for International Student Assessment (PISA) mathematics scores for 15-year-olds in 2003 and 2025. PISA measures how well 15-year-old students can apply their knowledge and skills to real-world problems.

The Top Scorers in Math in 2003

In 2003, the highest-performing education systems included a mix of European, Asia-Pacific, and North American economies.

Hong Kong led the participating economies in mathematics with an average score of 550, followed by Finland at 544 and South Korea at 542. The Netherlands, Liechtenstein, Japan, and Canada completed the top seven.

How the Ranking Shifted by 2025

By 2025, every economy in the top seven was located in Asia.

China, representing Beijing, Shanghai, Jiangsu, and Zhejiang, recorded the highest mathematics score at 612, while Singapore followed at 563. Across OECD countries as a whole, the average mathematics score stood at 463 in 2025.

Former Leaders Lose Ground

Several countries that ranked near the top in 2003 have moved down considerably.

Finland, which scored 544 in mathematics in 2003, recorded 469 in 2025.

Canada’s score fell from 532 to 485, while the Netherlands declined from 538 to 483.

The United States remains well outside the group of top-performing economies in mathematics. While American students perform more strongly in reading and science, math has historically been a weaker area in PISA assessments.

Math Scores Are Falling More Broadly

OECD data shows that the broader decline is continuing: average mathematics performance across 35 OECD countries fell another nine points between 2022 and 2025.

On a longer timeline, average mathematics scores fell by 22 points between 2015 and 2025, which the OECD estimates is equivalent to just over one year of learning.

PISA also found an association between heavy digital leisure use and student outcomes. Students spending more than four hours a day on digital leisure activities outside school tended to have lower mathematics scores and a weaker sense of belonging.

By contrast, moderate digital use was associated with better outcomes on both measures than either no use or very high use.

China’s Result Comes With an Important Caveat

China’s 2025 result does not represent the entire mainland Chinese student population.

The reported score covers Beijing, Shanghai, Jiangsu, and Zhejiang. These jurisdictions recorded an average mathematics score of 612, the highest in PISA 2025.

Learn More on the Voronoi App

If you enjoyed today’s post, check out Countries by Education Spending as % of GDP on Voronoi.

How Student Debt Varies Across the U.S.

Student debt can follow borrowers long after graduation, with balances shaped by factors ranging from education levels to where borrowers live.

This map shows average federal student loan debt per borrower using Federal Student Aid figures as of March 2026, compiled via the Education Data Initiative. Balances include principal and interest but exclude private student loans.

Where Student Loan Balances Are Highest

More than 40 million individuals, or about one in six American adults, have student debt today. Total federal student loan debt has surpassed $1.8 trillion, making it roughly comparable to the size of South Korea’s economy.

Washington, D.C., stands apart with an average balance of $55,846. Maryland, in a distant second, has the highest average among the 50 states at $45,589, followed by Georgia ($43,813), Virginia ($41,916), and Florida ($41,162).

The following data table ranks states by their average federal debt per borrower.

States in the country’s interior tend to have lower student debt averages. North Dakota ($30,543) is lowest nationwide, followed by South Dakota ($31,705) and Iowa ($31,885).

Geography can be misleading, however, because these figures are based on a borrower’s state of residence rather than the location of the college they attended. A state’s position therefore reflects the debt carried by people living there, not simply the tuition charged by local universities.

Why D.C. Stands Out

The nation’s capital has an average balance roughly $10,000 higher than the nearest state. One likely factor is D.C.’s high concentration of advanced-degree holders. The District leads the nation in higher education, including graduate education, as well as income, supported in part by high-paying government-adjacent private-sector jobs.

Two-thirds of adults in D.C. have a bachelor’s degree, while more than a third of residents aged 25 and older hold a graduate or professional degree. Meanwhile, median household income tops $109,000, well ahead of any state.

Graduate education, including master’s degrees and law school, can add another layer of borrowing after a bachelor’s degree. Borrowers with more education are more likely to carry larger student loan balances, meaning D.C.’s outlier figure may partly reflect its highly educated population and greater exposure to graduate-school borrowing.

Bigger Balances, Bigger Paychecks?

The D.C. example points to a broader consideration: loan size is only one part of the repayment challenge. Income, employment, and degree completion also matter.

Borrowers with less education are more likely to fall behind on student loan payments, even though they have often taken out less debt than those with more advanced degrees. A smaller loan can still be difficult to repay without the earnings that a completed degree may help provide.

This is important context given that more than 40% of students who attend college never graduate. That leaves millions of Americans carrying student debt without the potential earnings benefit of a completed degree.

Learn More on the Voronoi App

To explore which degrees are associated with the most debt, check out Ranked: Median Student Debt for a U.S. College Degree on Voronoi.