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April 21 (Reuters) - U.S. miner Arch Coal Inc reported a bigger-than-expected quarterly loss and cut its full-year production forecast for both power-generating and steel-making coal.
The company said on Tuesday that it now expects thermal coal production of 120-130 million tons, down from the 124-136 million tons it forecast in February.
Arch also cut its production forecast for metallurgical, or steel-making, coal to 6.0-6.8 million tons from 6.3-7.0 million tons.
The company, which mines coal in various regions in the United States such as Powder River Basin, Appalachia, Colorado and Illinois, said average sales price fell to $19.18 per ton in the first quarter from $20.09, a year earlier.
Coal miners have been under pressure as power utilities switch to cheaper natural gas and big consumers such as China reduce imports.
Prices of natural gas futures are down 11.6 percent this year to Monday's close.
The company's net loss narrowed to $113.2 million, or 53 cents per share, in the quarter ended March 31, from $124.1 million, or 59 cents per share, a year earlier.
On an adjusted basis, the company lost 54 cents per share, above analysts' average expectation of 48 cents, according to Thomson Reuters I/B/E/S.
Revenue fell 8 percent to $677 million, missing the average analyst estimate of $720.3 million.
Up to Monday's close, Arch Coal's shares had fallen about 41 percent this year.
(Reporting by Anet Josline Pinto in Bengaluru; Editing by Maju Samuel and Sriraj Kalluvila)