TransAlta (NYSE: TAC) reported earnings on July 30. Here are the numbers you need to know.

The 10-second takeaway
 For the quarter ended June 30 (Q2), TransAlta whiffed on revenues and missed estimates on earnings per share.

Compared to the prior-year quarter, revenue grew significantly. GAAP earnings per share expanded.

Margins grew across the board.

Revenue details
 TransAlta tallied revenue of $514.3 million. The one analyst polled by S&P Capital IQ looked for sales of $575.3 million on the same basis. GAAP reported sales were 29% higher than the prior-year quarter's $399.0 million.

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 $0.05. The five earnings estimates compiled by S&P Capital IQ predicted $0.16 per share. GAAP EPS were $0.05 for Q2 against -$3.44 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 40.6%, much better than the prior-year quarter. Operating margin was 17.2%, much better than the prior-year quarter. Net margin was 4.6%, much better than the prior-year quarter. (Margins calculated in GAAP terms.)

Looking ahead
 Next quarter's average estimate for revenue is $588.7 million. On the bottom line, the average EPS estimate is $0.16.

Next year's average estimate for revenue is $2.28 billion. The average EPS estimate is $0.68.

Investor sentiment
 The stock has a five-star rating (out of five) at Motley Fool CAPS, with 84 members out of 88 rating the stock outperform, and four members rating it underperform. Among 19 CAPS All-Star picks (recommendations by the highest-ranked CAPS members), 18 give TransAlta a green thumbs-up, and one give it a red thumbs-down.

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