The blue dots show the evolution of post-tax disposable income inequality based on Distributional National Accounts (DINA) for Belgium.

The red dots show the evolution of equivalized disposable household income based on income surveys. Most of the existing evidence about income inequality in Belgium is based on income surveys.

The Socio Economic Panel (SEP) is used for the years 1985, 1988, 1992 and 1997. The period 2003-2022 is based on the EU Statistics on Income and Living Conditions (EU-SILC).

There is a gap between the total income aggregate recorded in the income surveys and the macro-economi concept of net national income (NNI) recorded by the system of national accounts.

This implies that the existing evidence on income inequality is only based on a slice of the total income pie, available for redistribution among residents in a country. 

The essence of the DINA methodology is to distribute the entire income of an economy, not only the part registered in income surveys. 

The graph shows the evolution of NNI and different income components. The evolution of NNI is quite stable over time contraty to some of its components.

Net national income can be studied at different stages of the macro-economic circular flow of income, leading to four distinct income concepts in the DINA methodology.

1. Pre-tax factor income is paid out to the production factors labour and capital. At this tage there is no redistribution of any kind.

2. Pre-tax post-replacement income builds upon the pre-tax factor income by substracting social contributions and adding replacement benefits.

3. Post-tax disposable income is a post-tax-and-transfer concept. Starting from the previous concept, it substracts all remaining taxes and adds all remaining cash social benefits.
   Note that part of government revenue is not used for benefits but pays for in kind benefits and collective services. This is thus the only income concept that does not equal NNI. 

4. Post-tax national income includes not only cash benefits but also in kind benefits and collective services.

This graph compares inequality our figures for Belgium  (indicated with*) with figures published at the World Inequality Database (WID).