TransAlta (NYSE: TAC) is expected to report Q1 earnings on April 23. Here's what Wall Street wants to see:

The 10-second takeaway
 Comparing the upcoming quarter to the prior-year quarter, average analyst estimates predict TransAlta's revenues will shrink -10.9% and EPS will shrink 0.0%.

The average estimate for revenue is $585.4 million. On the bottom line, the average EPS estimate is $0.20.

Revenue details
 Last quarter, TransAlta logged revenue of $663.2 million. GAAP reported sales were 3.8% lower than the prior-year quarter's $689.6 million.

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

EPS details
 Last quarter, non-GAAP EPS came in at $0.21. GAAP EPS of $0.15 for Q4 were 36% higher than the prior-year quarter's $0.11 per share.

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

Recent performance
 For the preceding quarter, gross margin was 40.8%, 230 basis points better than the prior-year quarter. Operating margin was 19.2%, 10 basis points worse than the prior-year quarter. Net margin was 7.3%, 330 basis points better than the prior-year quarter.

Looking ahead

The full year's average estimate for revenue is $2.29 billion. The average EPS estimate is $0.79.

Investor sentiment
 The stock has a five-star rating (out of five) at Motley Fool CAPS, with 87 members out of 91 rating the stock outperform, and four members rating it underperform. Among 22 CAPS All-Star picks (recommendations by the highest-ranked CAPS members), 21 give TransAlta a green thumbs-up, and one give 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 $19.62.

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