- The data shows income thresholds for each decile (tenth of the population), sourced from the World Bank's Poverty and Inequality Platform using national surveys from high-income (after-tax income) and low/middle-income (consumption) countries, with adjustments for own-production and barter in lower-income nations.
- For consistency, only one data series (income or consumption) is kept per country-year, and regional/global estimates are extrapolated using national accounts growth forecasts, all expressed in constant international dollars to account for inflation and cost-of-living differences.
- The data processing involves extracting decile thresholds from auxiliary World Bank percentiles, calculating missing values via API queries, and pooling regional distributions, with country series sometimes adjusted to balance comparability and time length.