Quarterly financial reports play a vital role on Wall Street, as they help investors see how a company has performed and what might be coming down the road in the near-term. And out of all of the metrics and results to consider, earnings is one of the most important.We know earnings results are vital, but how a company performs compared to bottom line expectations can be even more important when it comes to stock prices, especially in the near-term. This means that investors might want to take advantage of these earnings surprises.Now that we know how important earnings and earnings surprises are, it's time to show investors how to take advantage of these events to boost their returns by utilizing the Zacks Earnings ESP filter.The Zacks Earnings ESP, ExplainedThe Zacks Earnings ESP is more formally known as the Expected Surprise Prediction, and it aims to grab the inside track on the latest analyst estimate revisions ahead of a company's report. The idea is relatively intuitive as a newer projection might be based on more complete information.With this in mind, the Expected Surprise Prediction compares the Most Accurate Estimate (being the most recent) against the overall Zacks Consensus Estimate. The percentage difference provides the ESP figure. The system also utilizes our core Zacks Rank to provide a stronger system for identifying stocks that might beat their next quarterly earnings estimate and possibly see the stock price climb.In fact, when we combined a Zacks Rank #3 (Hold) or better and a positive Earnings ESP, stocks produced a positive surprise 70% of the time. Perhaps most importantly, using these parameters has helped produce 28.3% annual returns on average, according to our 10 year backtest.Stocks with a ranking of #3 (Hold), or 60% of all stocks covered by the Zacks Rank, are expected to perform in-line with the broader market. Stocks with rankings of #2 (Buy) and #1 (Strong Buy), or the top 15% and top 5% of stocks, respectively, should outperform the market; Strong Buy stocks should outperform more than any other rank.Should You Consider ServiceNow?The last thing we will do today, now that we have a grasp on the ESP and how powerful of a tool it can be, is to quickly look at a qualifying stock. ServiceNow (NOW) holds a #3 (Hold) at the moment and its Most Accurate Estimate comes in at $1.86 a share 20 days away from its upcoming earnings release on October 26, 2022.NOW has an Earnings ESP figure of +0.35%, which, as explained above, is calculated by taking the percentage difference between the $1.86 Most Accurate Estimate and the Zacks Consensus Estimate of $1.85. ServiceNow is one of a large database of stocks with positive ESPs. Make sure to utilize our Earnings ESP Filter to uncover the best stocks to buy or sell before they've reported.NOW is just one of a large group of Computer and Technology stocks with a positive ESP figure. Hewlett Packard Enterprise (HPE) is another qualifying stock you may want to consider.Hewlett Packard Enterprise is a Zacks Rank #3 (Hold) stock, and is getting ready to report earnings on November 29, 2022. HPE's Most Accurate Estimate sits at $0.58 a share 54 days from its next earnings release.The Zacks Consensus Estimate for Hewlett Packard Enterprise is $0.57, and when you take the percentage difference between that number and its Most Accurate Estimate, you get the Earnings ESP figure of +1.75%.NOW and HPE's positive ESP metrics may signal that a positive earnings surprise for both stocks is on the horizon.Find Stocks to Buy or Sell Before They're ReportedUse the Zacks Earnings ESP Filter to turn up stocks with the highest probability of positively, or negatively, surprising to buy or sell before they're reported for profitable earnings season trading. Check it out here >> Zacks Names "Single Best Pick to Double" From thousands of stocks, 5 Zacks experts each have chosen their favorite to skyrocket +100% or more in months to come. From those 5, Director of Research Sheraz Mian hand-picks one to have the most explosive upside of all. It’s a little-known chemical company that’s up 65% over last year, yet still dirt cheap. With unrelenting demand, soaring 2022 earnings estimates, and $1.5 billion for repurchasing shares, retail investors could jump in at any time. This company could rival or surpass other recent Zacks’ Stocks Set to Double like Boston Beer Company which shot up +143.0% in little more than 9 months and NVIDIA which boomed +175.9% in one year.Free: See Our Top Stock And 4 Runners UpWant 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 ServiceNow, Inc. (NOW): Free Stock Analysis Report Hewlett Packard Enterprise Company (HPE): Free Stock Analysis Report To read this article on Zacks.com click here. Zacks Investment Research