Arch Coal (NYSE: ACI) reported earnings on Feb. 5. Here are the numbers you need to know.

The 10-second takeaway
 For the quarter ended Dec. 31 (Q4), Arch Coal missed estimates on revenues and missed expectations on earnings per share.

Compared to the prior-year quarter, revenue contracted significantly and GAAP earnings per share shrank to a loss.

Margins shrank across the board.

Revenue details
 Arch Coal tallied revenue of $968.2 million. The 12 analysts polled by S&P Capital IQ wanted to see revenue of $997.3 million on the same basis. GAAP reported sales were 21% lower than the prior-year quarter's $1.23 billion.

Source: S&P Capital IQ. Quarterly periods. Dollar amounts in millions. Non-GAAP figures may vary to maintain comparability with estimates.

EPS details
 EPS came in at -$0.42. The 22 earnings estimates compiled by S&P Capital IQ predicted -$0.14 per share. GAAP EPS were -$1.39 for Q4 against $0.28 per share for the prior-year quarter.

Source: S&P Capital IQ. Quarterly periods. Non-GAAP figures may vary to maintain comparability with estimates.

Margin details
 For the quarter, gross margin was 16.4%, 590 basis points worse than the prior-year quarter. Operating margin was 2.0%, 730 basis points worse than the prior-year quarter. Net margin was -30.5%, 3,530 basis points worse than the prior-year quarter.

Looking ahead
 Next quarter's average estimate for revenue is $961.5 million. On the bottom line, the average EPS estimate is -$0.29.

Next year's average estimate for revenue is $4.02 billion. The average EPS estimate is -$0.81.

Investor sentiment
 The stock has a three-star rating (out of five) at Motley Fool CAPS, with 1,486 members out of 1,562 rating the stock outperform, and 76 members rating it underperform. Among 334 CAPS All-Star picks (recommendations by the highest-ranked CAPS members), 318 give Arch Coal a green thumbs-up, and 16 give it a red thumbs-down.

Of Wall Street recommendations tracked by S&P Capital IQ, the average opinion on Arch Coal is hold, with an average price target of $8.29.

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