Trend in Productivity in Coal Mines in India (1951, 1956, 1961, 1966, 1971, 1976, 1981 and 1986 to 2015) | ||||||||
(In Tonne) | ||||||||
Years | Output per Manshift | Output per Man Year | ||||||
Below Ground | Open Cast | Below Ground and Open Cast | All in the Mine | Below Ground | Open Cast | Below Ground and Open Cast | All in the Mine |