Chancel, Lucas, and Thomas Piketty. "Indian Income Inequality, 1922-2014: From British Raj to Billionaire Raj?". Wealth and Income Database Working Paper, No.11 (2017).

Chancel, Lucas, and Thomas Piketty. "Indian Income Inequality, 1922-2014: From British Raj to Billionaire Raj?". Wealth and Income Database Working Paper, No.11 (2017).

• At the time of the introduction of income taxation in India in 1922, there was a highly unequal distribution of wealth, with the top 1% of Indians making up 13% of all income, not including wealth inequalities. This decreased from the 1950s onwards, to a low point of only 5% of income being controlled by the top 1% until the 1980s, when liberalization reforms caused an doubling of income inequality by the 21st Century (2).
• Income inequality have grown particularly among the top 1% of the population, whose share of national income increased from 6.2% prior to the 7th Five Year Plan to 21.7% in 2013 (18). This figure is equivalent to income inequality in India during the 1930s (19).
• Similar increases in income inequality since the 1980s are also observed among the top 0.1% of the population, which experienced a massive increase in share of wealth beginning in the 1980s and greatly accelerating in the 21st Century, reaching 8% of national income (20).
• The increase of income among the top decile of Indians has been mirrored by a decline in the income proportion of the middle two quintiles of Indians. The proportion of income for the middle 40% of Indians began to decline from an average of 45% in 1990s, with decline rapidly increasing in the 21st Century (22). The share of national income among the bottom half of Indians underwent a decline during the same period (23). 
• Indian growth rates have historically been slow, at around 2% since independence, but declining during the 1970s (6). They doubled in the 21st Century, to around 4% per annum (2). This increase in economic growth since the turn of the century registers across all groups, but is not significant enough to counteract the general decline in growth rates among the poor in the 1980s (3).
• This growth has, however, been unequally distributed. Since the 1980s, growth rates for the upper decile of the population has grown much more than average, a trend exacerbated among the top 1%, while growth rates for the bottom two quintiles have actually decreased (2). 
• Not all of this inequality may be explained by actual shifts in income, but by increased attention to enforcing the filing of income taxes during the 1980s and 1990s. This may have resulted in previously undeclared income appearing on income tax forms, amplifying the already stark increase in income inequality (30).
• The distribution of growth in India has been extremely unequal compared to China during the same period. Since 1980, the poorest 50% of India saw their incomes double, while the same group in China saw their incomes triple. Among the middle 40% of the population, the Chinese saw incomes increase at six times the rate of their Indian counterparts. At the same time, the income of the wealthiest Indians increased at a faster rate than the wealthiest Chinese (24).
• The disparity between the Indian and Chinese distribution of income growth was most pronounced among the middle 40% of the population, with this population benefitting six times as much in China. The bottom 50% of the population were similarly sidelined in both countries, although China experienced much more growth (24-25).
• Although the incomes of the middle 40% of Indians doubled since 1980, this rate of growth is very low for developing countries. The actual proportion of total growth concentrated among the middle class in India during this period was not only lower than China, but also lower than Europe and the USA (34).
• Growth rates in India were much more equal during the Nehruvian socialist period from the 1950s until the 1980s, with income growth being weighted slightly in favor of the bottom 90% of the population, although the middle 40% was still privileged compared to the bottom 50% of the population (27-28). 
• Initially, India was a semi-socialist state. Prime Minister Nehru nationalized many core elements of the economy, including agriculture and construction, and constructed a system of price controls and protectionist tariffs. This system also featured heavy regulation of the private sector and an extremely progressive tax regime (5).
• Liberalization in India began in 1985, when Prime Minister Rajiv Gandhi implemented the 7th Five Year Plan, which deregulated the private sector, relaxed restrictions on foreign borrowing and imports, and decreased taxation. In the late 1980s, India suffered a balance-of-payments crisis and accelerated its liberalization program in order to obtain IMF support (5).
• The first set of major economic reforms were implemented in 1991, focusing on the privatization of nationalized industries, the deregulation of the private sector and markets, ended price controls, and pruning the public sector. These reforms were carried out both by Prime Minister Rao and Prime Minister Vajpayee (5-6).
• The Indian government no longer releases its income tax records, making accurate calculation of income inequality difficult (2). There are a number of problems with the other types of data available to calculate these statistics (7-8, 12, 16).
• The cancellation of public income tax data in 2000 could be the result of a number of possible factors. The government could have simply lost interest in this data. Alternatively, this could reflect the difficult of sorting large volumes of data as the number of income tax payers has increased in both total and relative terms, from under 1% prior to the 1990s to 6% of the population in 2011 (8). 
• The general trends of income inequality in India are an increase in inequality during the 1920s and 1930s, then a slight decrease during the Second World War, followed by a massive decrease in inequality from the 1950s to the 1970s. Income inequality starts to increase in the early 1980s, then undergoes a massive increase in the 21st Century, surpassing the previous highs of inequality during the 1930s (31).
• The increase in equality beginning in the 1950s appears to be the direct result of government initiatives to reduce wealth disparities through socialist developmental policies and nationalization of industry, a process that gradually continued into the 1970s (32).
• The sudden increase in inequality in 1983 is a result of a major decrease in income tax rates that year, new incentives for elites to declare income on taxes, resulting in a spike in declared income inequalities, and a severe drought that hurt the incomes of the poorest during this year (33).
• The period of 'Shining India', characterized by high growth rates since the 1980s, really only exists for the top decile of Indians, constituting around 80 million adults, whereas the golden age of growth for the poor and middle classes was between the 1950s and the 1970s. Moreover, even within the top decile, there are sizable inequalities that favor the top 1% of the population (34).

India is worse that we thought, it is one of most unequal countries on Earth; on par with South America. What this shows is that most growth for middle class and poor Indians occurred during the Nehruvian socialist period, with both of these groups seeing a decline in growth rates since the 1980s. The real ones benefitting from liberalization have been the top decile, making India more unequal than any time since the consolidation of the British Raj.