What is the cause of black money increasing in India?

Answer 1

The main sources of black money in India include drug trafficking, corruption, land grabbing, unreported unorganized sector, running brothels etc. and the cause of increasing this is the concept of earning money with ease.

Tax evasion is unfortunately the fuel boosting the black money in Indian economy.

Another reason can be given of Corruption in Govt. sector. When people are of opinion that the tax they are paying will bring rarely any good to them and instead will be distributed among politicians and bureaucrats , they will surely be discouraged to pay tax and will save for themselves (thus creation of black money) for paying exorbitant costs of essential commodities and other services.