The Auto-Tires-Trucks group has plenty of great stocks, but investors should always be looking for companies that are outperforming their peers. Has NIO (NIO) been one of those stocks this year? Let's take a closer look at the stock's year-to-date performance to find out.NIO is one of 90 companies in the Auto-Tires-Trucks group. The Auto-Tires-Trucks group currently sits at #4 within the Zacks Sector Rank. The Zacks Sector Rank includes 16 different groups and is listed in order from best to worst in terms of the average Zacks Rank of the individual companies within each of these sectors.The Zacks Rank emphasizes earnings estimates and estimate revisions to find stocks with improving earnings outlooks. This system has a long record of success, and these stocks tend to be on track to beat the market over the next one to three months. NIO is currently sporting a Zacks Rank of #2 (Buy).The Zacks Consensus Estimate for NIO's full-year earnings has moved 41.60% higher within the past quarter. This is a sign of improving analyst sentiment and a positive earnings outlook trend.Our latest available data shows that NIO has returned about 373.38% since the start of the calendar year. Meanwhile, the Auto-Tires-Trucks sector has returned an average of -1.32% on a year-to-date basis. This means that NIO is outperforming the sector as a whole this year.To break things down more, NIO belongs to the Automotive - Foreign industry, a group that includes 20 individual companies and currently sits at #102 in the Zacks Industry Rank. This group has lost an average of 5.21% so far this year, so NIO is performing better in this area.Going forward, investors interested in Auto-Tires-Trucks stocks should continue to pay close attention to NIO as it looks to continue its solid performance.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 NIO Inc. (NIO): Free Stock Analysis Report To read this article on Zacks.com click here.