The world’s largest coal miner said net profit for its fiscal first quarter fell to 37.31 billion rupees ($612 million) from 44.69 billion rupees a year earlier.

Net profit last quarter was 54.13 billion rupees.

The state-owned miner blamed the decline on lower sales, which fell to 164.7 billion rupees from 165 billion rupees last year.

Raw coal production was almost identical to the same quarter last year, at just under 103 million tons.

For the full 2012-13 fiscal year, the company produced 452 million tons of coal, falling just short of its target.

Employee expenses rose by 4.25 billion rupees compared with the same period last year, the result of a wage increase the company signed with its 375,000 workers last year.

Coal India produces about 80% of the country’s total coal output but has been plagued with regulatory and environmental hurdles that have prevented the growth required to meet increasing domestic demand.

Coal India shares fell 5.7% percent to 254.60 rupees in Mumbai on Friday ahead of the announcement Saturday. The stock has lost a quarter of its value so far in 2013, compared with a 1.4% drop in the benchmark S&P BSE Sensex index.