The country's economic situation is measured through a method called GDP known as "Gross Domestic Product" which is based on per capita income.
Actually economic situation not only depends on income unequality but also depends on wealth unequality, which is double than the income unequality. In simple way you may say that income equality has some way shorter effect and wealth has some longer economic effect. So its necessary to understand both in order to study, measure and improve the economic development.
According to study by OECD, it's analyzed that household wealth across 28 countries , is twice the level of income inequality on average. And its also found that 10% of household have 56% of the total wealth. In order to understand the GDP we have to study the correlation between income and wealth distribution among specific country.
And one more thing to consider is that this is not one country issue actually this OECD study was done through out the world, and even having highest GDP country like America have the same issue and the bottom 60 percent of U.S. households only hold 2.4 percent of household wealth.
And same issue is by many other top developed countries like Denmark, Germany and many other countries from Europe and America. This wealth distribution can be studied by following infographics.
Please do comment your response to this study as I am interested to see what you think on this correlation between income and wealth correlation.