Southwest Airlines Co. ‘s LUV shares have declined 14.7% in the past six months compared with a 14.2% fall of the industry it belongs to.Image Source: Zacks Investment ResearchCoronavirus-led low air-travel demand has resulted in Southwest Airlines incurring a loss for six successive quarters. Adding to its woes, the spread of the Delta variant is likely to dampen the September-quarter results. Management now expects third-quarter 2021 operating revenues to plunge in the 18-20% range from third-quarter 2019 actuals (former view was a 15-20% decline). Operating revenues for October are also expected to decline between 20% and 30%.Rising fuel prices hurt the airline’s bottom-line results. Fuel cost per gallon (inclusive of fuel tax: economic) rose 44.4% year over year to $1.92 in the second quarter. The airline anticipates economic fuel costs per gallon in the range of $2.05-$2.15 in both the third and the fourth quarters of 2021. The company’s current year bottom-line results have widened from a loss of $1.23 per share to a loss of $1.87 in the past 60 days. Moreover, Southwest Airlines, currently carrying a Zacks Rank# 4 (Sell), has a Momentum Score of F. This reflects on the stock’s short-term unattractiveness. In view of the above-mentioned headwinds, we believe that investors should get rid of the stock from their respective portfolios. You can see the complete list of today’s Zacks #1 Rank (Strong Buy) stocks here.Stocks to ConsiderSome better-ranked stocks in the broader Zacks Transportation sector are Schneider National, Inc. SNDR, Landstar System, Inc. LSTR and TFI International Inc. TFII. All the stocks carry a Zacks Rank #2 (Buy).Long-term expected earnings per share (three to five years) growth rate for Schneider National, Landstar and TFI International is pegged at 17.9%, 12% and 31.6%, respectively. Infrastructure Stock Boom to Sweep America A massive push to rebuild the crumbling U.S. infrastructure will soon be underway. It’s bipartisan, urgent, and inevitable. Trillions will be spent. Fortunes will be made. The only question is “Will you get into the right stocks early when their growth potential is greatest?” Zacks has released a Special Report to help you do just that, and today it’s free. Discover 7 special companies that look to gain the most from construction and repair to roads, bridges, and buildings, plus cargo hauling and energy transformation on an almost unimaginable scale.Download FREE: How to Profit from Trillions on Spending for Infrastructure >>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 Southwest Airlines Co. (LUV): Free Stock Analysis Report Landstar System, Inc. (LSTR): Free Stock Analysis Report Schneider National, Inc. (SNDR): Free Stock Analysis Report TFI International Inc. (TFII): Free Stock Analysis Report To read this article on Zacks.com click here.