Research Methodology: Appendices

Lower wealth threshold: There is a close link between financial assets and the incomes of private households. According to Davies et al. (2009)⁶, private individuals with below-average income tend to have no assets at all, or only very few. It is only when individuals move into middle and higher income groups that they start to accumulate substantial assets.

We have applied this link to our analysis. Countries in the upper-middle income bracket (based on the World Bank's country classification system) therefore form the group in which the average household assets first reach a meaningful level. This value marks the lower threshold for the global middle wealth class.

In terms of income, households with incomes that correspond to between 75% and 150% of average net income are generally considered to constitute the middle class. According to Davies et al., households with income corresponding to 75% of the average income have assets that correspond to 30% of the average assets. As far as the upper threshold is concerned, 150% of average income corresponds to 180% of average assets. Consequently, we have set the threshold values for the wealth middle class at 30% and 180% of average net financial assets per capital. In 2025, average net financial assets per capita in the countries covered stood at approximately EUR36,690. Applying these percentages gives the rounded thresholds used in the workbook: EUR11,000 and EUR66,000. Individuals with net financial assets between these thresholds belong to the global middle-wealth class. Those below the lower threshold belong to the low-wealth class, while those above the upper threshold belong to the high-wealth class.