The numbers on the GP's page include the value of government benefits. If you exclude the European social benefits, their median disposable income is even lower.

>The following table represents data from OECD's "median disposable income per person" metric, which includes all forms of income as well as taxes and transfers in kind from governments for benefits such as healthcare and education and is equivalised by dividing by the square root of household size. This metric, in addition to using a median rather than a mean, uses "data calculated according to the new OECD terms of reference"; compared to previous terms of reference, these "include a more detailed breakdown of current transfers received and paid by households as well as a revised definition of household income, including the value of goods produced for own consumption as an element of self-employed income." As OECD displays median disposable incomes in each country's respective currency, the values were converted here using the World Bank's PPP conversion factors, accounting for each country's cost of living in the year that the disposable median income was recorded. Unless noted otherwise, all data refers to 2019. Data are in United States dollars at current prices and current purchasing power parity for private consumption for the reference year.