MarkWest Energy Partners (NYSE: MWE) reported earnings on May 8. Here are the numbers you need to know.

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

Compared to the prior-year quarter, revenue grew. Non-GAAP earnings per share contracted significantly. GAAP earnings per share shrank to a loss.

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

Revenue details
 MarkWest Energy Partners logged revenue of $376.0 million. The five analysts polled by S&P Capital IQ foresaw revenue of $414.0 million on the same basis. GAAP reported sales were 5.8% lower than the prior-year quarter's $399.2 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 $0.11. The 12 earnings estimates compiled by S&P Capital IQ averaged $0.26 per share. Non-GAAP EPS of $0.11 for Q1 were 76% lower than the prior-year quarter's $0.46 per share. GAAP EPS were -$0.12 for Q1 against $0.14 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 59.4%, 190 basis points worse than the prior-year quarter. Operating margin was 17.2%, 410 basis points better than the prior-year quarter. Net margin was -4.1%, 810 basis points worse than the prior-year quarter. (Margins calculated in GAAP terms.)

Looking ahead
 Next quarter's average estimate for revenue is $428.3 million. On the bottom line, the average EPS estimate is $0.27.

Next year's average estimate for revenue is $1.84 billion. The average EPS estimate is $1.37.

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 $61.73.

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