Republic of uzbekistan ministry of higher education, science and innovations

Unemployment rate: 4.3%.

GDP per capita: $39 425.

Poverty rate: 11.1%.

Russia

• 
  Post-tax Gini coefficient: 0.38.
  
• 
  Unemployment rate: 5.2%.
  
• 
  GDP per capita: $24 417.
  
• 
  Poverty rate: NA.
  

Occupying the 11th place in the ranking of income inequality in the world. USA TODAY stated: "Russia has a Corruption Perceptions Index score of 28 – tied for the worst among OECD member states and affiliates and one of the lowest in the world. " The cause of the income gap are the close connections of Russian oligarchs and the government, thanks to these relationships oligarchs get lucrative business deals and earn more and more money.

South Africa

• 
  Post-tax Gini coefficient: 0.62.
  
• 
  Unemployment rate: 27.3%.
  
• 
  GDP per capita: $12 287.
  
• 
  Poverty rate: 26.6%.
  

The highest income inequality is in the South Africa, based on 2019 data. It is due to the recent policy of apartheid. There were huge differences between white and the other people, not only in wages, but also in the place they can enter and so on.

Other

High income inequality appears in China, India, Costa Rica, Brazil, Mexico, Chile, Turkey, Lithuania, South Korea, New Zealand and Latvia too.

Development of income distribution as a stochastic process

It is difficult to create a realistic and not complicated theoretical model, because the forces determining the distribution of income (DoI) are varied and complex and they continuously interact and fluctuate.
In a model by Champernowne, the author assumes that the income scale is divided into an enumerable infinity of income ranges, which have uniform proportionate distribution. The development through time of the DoI between ranges is regarded to be a stochastic process. The income of any person in one year may depend on the income in the previous year and on a chance of progress. Assuming that to every "dying" income receiver, there is an heir to his or her income in the following year, and vice versa. This implies that the number of incomes is constant through time.