Questar Corp. STR, a natural gas-focused energy company, reported adjusted first-quarter earnings of 50 cents per share, in line with the Zacks Consensus Estimate but higher than the year-ago quarter adjusted profit of 48 cents.Strong customer growth, higher rates, together with continued implementation of efficiency measures buoyed the results, partially offset by the challenging commodity market.Questar reported first-quarter revenues of $456.3 million, up 6% from a year ago. However, quarterly revenues failed to meet the Zacks Consensus Estimate of $496 million.Segment AnalysisQuestar Gas: The segment generated $407.9 million in revenues, up 9% from the prior-year quarter, owing to strong client growth. As of Mar 31, 2016, Questar Gas served more than 995,800 customers, up 2.1% from the year ago. This helped improve margins on the back of which the segment reported operating income of $83.4 million, 9% above the year-ago quarter profit of $76.6 million. The segment’s successful infrastructure-replacement program also supported earnings.Wexpro: Segment revenues decreased 44% year over year to $3.5 million in the quarter. Segmental operating income from continuing operations also fell to $39.7 million from $41.7 million in the prior-year quarter, hamstrung by lower average investment base and decline in oil revenues.Quarterly production of natural gas was down 4% to 14.4 billion cubic feet (Bcf) from 15.0 Bcf.Questar Pipeline: The segment reported revenues of $43.0 million against $46.8 million in the comparable quarter last year due to lower transportation and natural gas liquids sales. Nevertheless, income from continuing operations improved slightly (by $0.2 million) from first quarter 2015 to $27.6 million. Lower costs favorably affected the result.Total natural gas transportation volumes were $205.9 million decatherms, compared with 213.6 million decatherms in the first quarter of 2015.Expense SummaryAt $29.6 million, the general and administrative expenses for the quarter remained essentially flat, while depreciation, depletion and amortization costs rose 3% to $55.9 million. Total operating expense of $320.9 million marked an increase from the year-ago period level of $281.6 million owing to higher cost of sales.FinancialsAs of Mar 31, 2016, Questar had long-term debt (including current portion) of $993.9 million, with a debt-to-capitalization ratio of 42.2%.2016 Guidance MaintainedFor 2016, Questar stuck to its earnings per diluted share projection in the range of $1.25–$1.35.Zacks RankQuestar – which has entered into a $4.4 billion merger deal with Dominion Resources Inc. D – currently carries a Zacks Rank #3 (Hold). Meanwhile, one can look at better-ranked players in the same industry like ONE Gas Inc. OGS and Southwest Gas Corp. SWX. Both carry Zacks Rank #2 (Buy).Want the latest recommendations from Zacks Investment Research? Today, you can download 7 Best Stocks for the Next 30 Days. Click to get this free report >>Want the latest recommendations from Zacks Investment Research? Today, you can download 7 Best Stocks for the Next 30 Days. Click to get this free report DOMINION RES VA (D): Free Stock Analysis Report SOUTHWEST GAS (SWX): Free Stock Analysis Report QUESTAR (STR): Free Stock Analysis Report ONE GAS INC (OGS): Free Stock Analysis Report To read this article on Zacks.com click here.