The influence of the incomes of residents of any country on the consumer market, as a rule, is due to a sufficiently large number of factors that do not always find their place in theoretical descriptions. Not only macroeconomic characteristics of the region, and not even microeconomic ones, are important here; factors of a socio-historical and psychological nature are important here. What is the differentiation of incomes of the population, and how it affects the consumer market, can be clearly seen on the example of assessing the income of the population of the Grodno region of Belarus. This monitoring showed that over the period from 2008 to 2010, the region has seen a growth trend in both nominal and real values, but at the same time, their growth rates are slowing down from year to year, and the average per capita income is decreasing. On the whole, over the period 2008–2010, the nominal incomes of residents of the Grodno region increased 2.77 times. Moreover, their increase was not due to an increase in wages and other payments, but also due to a decrease in inflation growth rates, in connection, and therefore real incomes increased 1.55 times and income differentiation decreased.
Along with the growth in the value of cash incomes, the values of normative consumer baskets are also growing . The value of the subsistence minimum (BPM) per capita for the reporting period increased by 3.48 times, which exceeded slightly higher than the rate of increase in income and led to a sharp decrease in the population with incomes less than BMP, and, accordingly, in the region income differentiation declined.
Whereas in 2008, in the Grodno region, 24.6% of the population was below the subsistence minimum, in 2010 this value was only 6%. In addition, over the indicated period, statistics show an increase in the distance between BMPs and average estimated disposable incomes of the population. Based on this, it can be argued that in the field of income differentiation is steadily decreasing, poverty is decreasing and trends are emerging that indicate the formation of the middle class, which in the social sense constitutes the main segment of the consumer market.
Parameters of cash income determines the amount of consumer spending, part of which is directed to the purchase of goods for personal consumption and payment for services, i.e. represents the value of purchasing funds, which on average for the period 2008 - 2011 in the Grodno region amounted to about 80% of the amount of cash income. As part of the latter, expenditures on the purchase of products in the region amounted to about 40%, which may, although indirectly, serve as evidence of a fairly high level of income.
Moreover, if this indicator in 2008 amounted to 47%, then by 2011 it had dropped to 39.9%. The share of expenditures of the population of the Grodno region for the purchase of products is 2.7% lower than the national average.
Revenue growth favorably reflected in the amount of realized demand, which can be estimated by the indicator of retail turnover. The dynamics of the volume of retail trade turnover of the Grodno region indicates certain positive changes in the regional consumer market: for the period 2008 - 2011, retail trade turnover increased 1.68 times. Such data indicate that the differentiation of household incomes is a dynamic indicator of the level of real incomes of the population and is manifested through the absolute values and structure of consumption in the market of consumer services and goods. The establishment of a direct interdependence between income levels, the degree of activity in the consumer market and the social structure of the region’s population is also important.