MarkWest Energy Partners (NYSE: MWE) reported earnings on May 7. Here are the numbers you need to know.

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

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

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

Revenue details
MarkWest Energy Partners booked revenue of $350.5 million. The four analysts polled by S&P Capital IQ anticipated sales of $414.4 million on the same basis. GAAP reported sales were 0.4% higher than the prior-year quarter's $348.9 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 $0.46. The six earnings estimates compiled by S&P Capital IQ averaged $0.56 per share. GAAP EPS were $0.14 for Q1 against -$1.12 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 55.9%, 10 basis points worse than the prior-year quarter. Operating margin was 15.0%, 1,880 basis points better than the prior-year quarter. Net margin was 4.6%, 2,870 basis points better than the prior-year quarter.

Looking ahead
Next quarter's average estimate for revenue is $425.8 million. On the bottom line, the average EPS estimate is $0.56.

Next year's average estimate for revenue is $1.74 billion. The average EPS estimate is $2.42.

Investor sentiment
Of Wall Street recommendations tracked by S&P Capital IQ, the average opinion on MarkWest Energy Partners is outperform, with an average price target of $64.75.

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