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what is the total number of passenger coaches owned by indian railways
As of March 2017, Indian Railways' rolling stock includes 70,937 passenger coaches.
Who is the minister of the Indian railways system
Piyush Vedprakash Goyal (born 13 June 1964) is an Indian politician and the current minister of Railways and Commerce in the Government of India.
what is the annual revenue of the Indian Railways system
Indian Railways' revenue was US$28 billion for 2018-19.
what is the parent of the Indian Railways system
The Ministry of Railways is a ministry in the Government of India, which operates the state-owned Indian Railways.

Question: who is the chairman of the system
Self-contained rewrite: who is the chairman of the Indian Railways system