Alliant Energy (NYSE: LNT) reported earnings on May 4. Here are the numbers you need to know.

The 10-second takeaway
 For the quarter ended March 31 (Q1), Alliant Energy missed estimates on revenues and whiffed on earnings per share.

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

Gross margins increased, operating margins dropped, net margins contracted.

Revenue details
 Alliant Energy booked revenue of $765.7 million. The three analysts polled by S&P Capital IQ predicted sales of $822.1 million on the same basis. GAAP reported sales were 19% lower than the prior-year quarter's $945.0 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 $0.50. The six earnings estimates compiled by S&P Capital IQ predicted $0.63 per share. GAAP EPS of $0.32 for Q1 were 52% lower than the prior-year quarter's $0.66 per share. (The prior-year quarter included $0.01 per share in earnings from discontinued operations.)

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 26.6%, 140 basis points better than the prior-year quarter. Operating margin was 12.5%, 160 basis points worse than the prior-year quarter. Net margin was 4.6%, 320 basis points worse than the prior-year quarter.

Looking ahead
 Next quarter's average estimate for revenue is $686.3 million. On the bottom line, the average EPS estimate is $0.44.

Next year's average estimate for revenue is $3.31 billion. The average EPS estimate is $2.88.

Investor sentiment
 The stock has a three-star rating (out of five) at Motley Fool CAPS, with 77 members out of 89 rating the stock outperform, and 12 members rating it underperform. Among 31 CAPS All-Star picks (recommendations by the highest-ranked CAPS members), 26 give Alliant Energy a green thumbs-up, and five give it a red thumbs-down.

Of Wall Street recommendations tracked by S&P Capital IQ, the average opinion on Alliant Energy is outperform, with an average price target of $46.13.

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