The Common Human Development Index is an expansion of the Human Development Index, incorporating the social pillar, to foster development in terms of a country's overall happiness, moving beyond individualism.
The Common Human Development Index (CHDI) extends the UNDP Human Development Index by adding a social participation pillar to the traditional dimensions of health, education, and income.
Grounded in the capability approach and the concept of development as happiness, the CHDI captures how belonging, civic engagement, and volunteering contribute to human flourishing.
The CHDI thus redefines human development as a shared, relational process—beyond individualism—integrating the social dimension into a measurable composite index
Authors: Demetrio M. Bova, Leonardo Becchetti, Luca Raffaele, Lorenzo Semplici
The comparison between the HDI and CHDI rankings reveals both common patterns and marked differences. The most notable case is Italy, which drops ten positions (from 17th to 27th) when the social component is included. Spain and Germany follow, each losing five positions, while Greece falls by four, Türkiye by three, and France by one. These results suggest that the inclusion of the social dimension tends to penalize larger countries, possibly because their size and internal heterogeneity weaken the social pillar.
Conversely, Poland and Malta each gain five positions, followed by the Netherlands, Cyprus, Luxembourg, Finland, Estonia, and Slovenia, all of which improve their relative standing. This pattern supports the hypothesis that smaller countries tend to perform better when the social pillar is considered—summarized by the notion that “the smaller, the stronger the social dimension.”
The inclusion of civic participation substantially increases the human development index ability to explain life satisfaction, even though CHDI and HDI share their fundamental structure. CHDI incorporates the social pillar as a core component of development, reflecting the idea that human flourishing depends not only on income, education, and health but also on belonging, participation, and civic connection.
Although HDI remains a powerful and well-established indicator of development, the CHDI achieves a superior explanatory performance with a statistically significant improvement in R² and a lower AIC. This suggests that the civic component provides genuine, non-redundant information about what drives subjective well-being across countries.
By integrating social participation into the measurement of human progress, CHDI moves closer to a holistic understanding of development, one that encompasses not only having and being, but also belonging and acting together.
The Common Human Development Index (CHDI) extends the UN HDI by adding a fourth pillar, Participation (P), to the standard Education (E), Health (H), and Income (I) dimensions.
E, H, I: we use the official HDI component indices as rescaled by UNDP (education index; life-expectancy index; income index with log treatment), aligned to the UNDP methodology and 2022 reference year where jointly available.
P (Participation): share of people reporting formal or informal volunteering and/or active citizenship, from Eurostat ilc_scp21 (2022).
𝐻𝐷𝐼=(𝐸×𝐻×𝐼)^(1/3)
𝐶𝐻𝐷𝐼=(𝑃×𝐸×𝐻×𝐼)^(1/4)
They use the geometric mean to keep dimensions complementary and to avoid full compensability.
Rescaling of P between 0 and 1 accounts for decreasing marginal returns. It follows a formula similar to the Gross National Income rescaling in HDI.
𝑃=(ln(𝑃articipation*100 + 1)−ln(1))/(ln(101)−ln(1))
E, H, I & HDI reference: UN/World Bank/UNDP-aligned series used for the HDI components and normalization scheme (education index, life-expectancy index, income index with log treatment), year: 2022 where jointly available.
P: Eurostat QoL module, ilc_scp21 (share in formal/informal volunteering or active citizenship), year: 2022.
UNDP (2023). Human Development Report 2023/24 (HDI methodology and component rescaling).
World Bank (2024). Human Development Index/ Education / Life Expectancy / GNI datasets (HDI inputs, 2022).
Eurostat (2022). ilc_scp21: Social participation by frequency of participation in voluntary activities.
Eurostat (2022), indicatore ilc_pw01 – Overall life satisfaction (scale 0–10), Quality of life – Overall experience of life.
Bova & Becchetti (2025). Common Human Development Index: The Sense of Community Predicts Better Happiness (concept and empirical validation).
