TransAlta (NYSE: TAC) reported earnings on Aug. 1. 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 expectations on earnings per share.

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

Margins contracted across the board.

Revenue details
TransAlta reported revenue of $399.0 million. The three analysts polled by S&P Capital IQ hoped for sales of $537.3 million on the same basis. GAAP reported sales were 25% lower than the prior-year quarter's $534.0 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 -$0.10. The eight earnings estimates compiled by S&P Capital IQ anticipated -$0.06 per share. GAAP EPS were -$3.44 for Q2 versus $0.06 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 28.7%, 990 basis points worse than the prior-year quarter. Operating margin was -6.6%, 2,140 basis points worse than the prior-year quarter. Net margin was -194.3%, 19,720 basis points worse than the prior-year quarter.

Looking ahead
Next quarter's average estimate for revenue is $606.7 million. On the bottom line, the average EPS estimate is $0.24.

Next year's average estimate for revenue is $2.44 billion. The average EPS estimate is $0.73.

Investor sentiment
The stock has a five-star rating (out of five) at Motley Fool CAPS, with 81 members out of 85 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 gives it a red thumbs-down.

Of Wall Street recommendations tracked by S&P Capital IQ, the average opinion on TransAlta is hold, with an average price target of $21.96.

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