NRG Energy (NYSE: NRG) reported earnings yesterday. Here are the numbers you need to know.

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

Compared to the prior-year quarter, revenue increased significantly, and GAAP loss per share improved.

Margins dropped across the board.

Revenue details
NRG Energy recorded revenue of $2.13 billion. The four analysts polled by S&P Capital IQ expected to see sales of $3.28 billion on the same basis. GAAP reported sales were 17% higher than the prior-year quarter's $1.82 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 -$0.48. The eight earnings estimates compiled by S&P Capital IQ anticipated -$0.16 per share. GAAP EPS were -$0.48 for Q4 versus -$0.07 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 20.7%, 940 basis points worse than the prior-year quarter. Operating margin was 0.4%, 800 basis points worse than the prior-year quarter. Net margin was -5.1%, 430 basis points worse than the prior-year quarter.

Looking ahead
Next quarter's average estimate for revenue is $2.34 billion. On the bottom line, the average EPS estimate is $0.04.

Next year's average estimate for revenue is $9.34 billion. The average EPS estimate is $0.92.

Investor sentiment
The stock has a five-star rating (out of five) at Motley Fool CAPS, with 720 members rating the stock outperform and 14 members rating it underperform. Among 229 CAPS All-Star picks (recommendations by the highest-ranked CAPS members), 226 give NRG Energy a green thumbs-up, and three give it a red thumbs-down.

Of Wall Street recommendations tracked by S&P Capital IQ, the average opinion on NRG Energy is outperform, with an average price target of $24.88.

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