In modern societies, adults are confronted with ever-increasing amounts of information of a quantitative or mathematical nature, which they often need to access online or through digital devices. This information must be located, selected or filtered, interpreted, and at times questioned, and analysed for their relevance to the responses needed. To reflect real-world demands, the PIAAC assessment use a variety of item types, including interactive calculators, interactive charts and data, or simple spreadsheets. The results of the assessment are reported in six proficiency levels (below Level 1 to Level 5), with accurate descriptions of the types of tasks that adults at different levels are able to perform successfully.
Adult numeracy skills
The 2023 Survey of Adult Skills (PIAAC Cycle 2) defines numeracy as accessing, using, and reasoning critically with mathematical content, information and ideas represented in multiple ways in order to engage in and manage the mathematical demands of a range of situations in adult life. The Survey assesses and describes the numeracy skills of adults aged 16-65.
Key messages
Modern societies and workplaces present adults with an increasing amount and variety of information of a quantitative or mathematical nature. The Survey shows that numeracy is often strongly associated with the probability of being employed and earning higher wages. For example, across participating OECD countries and economies a one-standard-deviation increase in numeracy is associated with a 9% increase in hourly wages (while for literacy the associated increase in wages is 8%),. The association between numeracy and wages is particularly strong (15%) in England (UK) and Chile.
On average, across OECD countries that participated in PIAAC Cycle 2, 25 percent of adults have low proficiency in numeracy (meaning they score at Level 1 or below on the PIAAC numeracy scale). In numeracy, adults at Level 1 can only do basic calculations with whole numbers or money, understand decimals, and find single pieces of information in tables or charts, but they may struggle with tasks needing multiple steps. Those below Level 1 can only add and subtract small numbers. The share of low proficient adults range from 10 percent in Japan to 56 percent in Chile.
On average, across OECD countries that participated in PIAAC Cycle 2, only 14 percent scored at Levels 4 or 5, the highest proficiency levels of numeracy. Adults at Levels 4 or 5 are top performers. They can calculate and understand rates and ratios, interpret complex graphs, and critically evaluate statistical claims. In Finland, 31 percent of adults score at the highest numeracy levels; this share is at least 20 percent in Denmark, Estonia, the Flemish Region (Belgium), Japan, the Netherlands, Norway, Singapore, Sweden, and Switzerland.
Context
The link between numeracy, education and employment is weaker in 2023 than it was ten years ago
Skills continue to play a big role in employability, over and above education. Having better skills and spending more time in education both help people get jobs, but this link is not as strong as it was a decade ago. Tighter labour markets in 2023 might explain this shift. An increase of one standard deviation in numeracy skills (58 points) and in years of education (3 years) are both associated with an increase of around 1 percentage point in the likelihood of being employed. Countries like England (UK), Italy, and Spain show the clearest connection between numeracy skills and employment.
Eight countries have seen improvements in average numeracy proficiency in the past decade
Across 27 countries that participated in both cycles of the Survey of Adult Skills, eight countries have seen average numeracy scores improve, with the largest gains recorded in Finland and Singapore (both 17 points). Average scores remained stable in 12 countries and declined in 7, most significantly in Lithuania and Poland. Overall, changes in numeracy have been more favourable than in literacy, where more countries have seen widespread declines.
