Based on an SBI report, internal migration increased state GDP by Rs 15 lakh crore. According to the report, the increase in productivity due to human resource redistribution far outweighs the loss in GDP of states where people are leaving.

The report looks at income tax returns to see how circular migration affects the rise of the middle class. The weighted average income of Rs 4.4 lakh in 2014 has increased to Rs 13 lakh. With the distribution of tax filers shifting from lower-income to upper-income groups, it will rise to Rs 49.7 lakh by 2047.

According to the report, six major Indian states - Delhi, Tamil Nadu, Kerala, Gujarat, Karnataka, and Maharashtra - have net positive migration. According to the analysis, the migrant population contributed 0.5-2.5% of GSDP, for a total contribution of around 7.8% (roughly Rs 15 lakh crore). UP, Bihar, Rajasthan, Madhya Pradesh, Odisha, Andhra Pradesh, and West Bengal are the states with the highest negative migration rates.

According to an SBI report, nearly 25% of income tax filers are expected to leave the lowest income bracket by FY47, compared to 13.6% leaving the same bracket between assessment years 12-23. "Weighted mean income of Rs 4.4 lakh in AY14 (based on ITR returns) has increased to Rs 13 lakh (aided by transition from lower to upper income group as well as buoyancy in the number of tax-filers who were previously not reporting income) and to Rs 49.7 lakhs in 2047 with the shifting of distribution of tax-filers from lower to upper income," according to the report.