New Jersey Resources (NJR) could be a solid addition to your portfolio given a notable revision in the company's earnings estimates. While the stock has been gaining lately, the trend might continue since its earnings outlook is still improving.The upward trend in estimate revisions for this energy services holding company reflects growing optimism of analysts on its earnings prospects, which should get reflected in its stock price. After all, empirical research shows a strong correlation between trends in earnings estimate revisions and near-term stock price movements. Our stock rating tool -- the Zacks Rank -- is principally built on this insight.The five-grade Zacks Rank system, which ranges from a Zacks Rank #1 (Strong Buy) to a Zacks Rank #5 (Strong Sell), has an impressive externally-audited track record of outperformance, with Zacks #1 Ranked stocks generating an average annual return of +25% since 2008.For New Jersey Resources, there has been strong agreement among the covering analysts in raising earnings estimates, which has helped push consensus estimates considerably higher for the next quarter and full year.The chart below shows the evolution of forward 12-month Zacks Consensus EPS estimate:12 Month EPSCurrent-Quarter Estimate RevisionsThe earnings estimate of $0.42 per share for the current quarter represents a change of +500% from the number reported a year ago.The Zacks Consensus Estimate for New Jersey Resources has increased 62.82% over the last 30 days, as one estimate has gone higher while one has gone lower.Current-Year Estimate RevisionsFor the full year, the company is expected to earn $2.43 per share, representing a year-over-year change of +12.5%.In terms of estimate revisions, the trend for the current year also appears quite encouraging for New Jersey Resources. Over the past month, three estimates have moved higher compared to no negative revisions, helping the consensus estimate increase 5.36%.Favorable Zacks RankThanks to promising estimate revisions, New Jersey Resources currently carries a Zacks Rank #2 (Buy). The Zacks Rank is a tried-and-tested rating tool that helps investors effectively harness the power of earnings estimate revisions and make the right investment decision. You can see the complete list of today's Zacks #1 Rank (Strong Buy) stocks here.Our research shows that stocks with Zacks Rank #1 (Strong Buy) and 2 (Buy) significantly outperform the S&P 500.Bottom LineInvestors have been betting on New Jersey Resources because of its solid estimate revisions, as evident from the stock's 9.5% gain over the past four weeks. As its earnings growth prospects might push the stock higher, you may consider adding it to your portfolio right away. How to Profit from the Hot Electric Vehicle Industry Global electric car sales in 2021 more than doubled their 2020 numbers. And today, the electric vehicle (EV) technology and very nature of the business is changing quickly. The next push for future technologies is happening now and investors who get in early could see exceptional profits. See Zacks' Top Stocks to Profit from the EV Revolution >>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 NewJersey Resources Corporation (NJR): Free Stock Analysis Report To read this article on Zacks.com click here. Zacks Investment Research