Central Coalfields Ltd – a wholly-owned subsidiary of Coal India Ltd – has posted a 21 per cent increase in profit before tax (PBT) to Rs 1,860 crore in 2010-11. During the year, coal production was up one per cent to 47.52 million tonnes. Coal dispatch increased 4.5 per cent to 46 mt. Overburden removal increased by over 11 per cent to 62.52 mt.