Capacity-related woes have been hurting Allegiant Travel Company ALGT for quite some time. In fact, it is one of the factors behind the 3.4% decline in the company’s stock price so far this year. The company’s May traffic report was no exception and showed substantial year-over-year rise in capacity.Detailed ReportTraffic for the total system that includes scheduled service and fixed fee contract — measured in revenue passenger miles (RPMs) — increased 10.9% on a year-over-year basis to 1.06 billion. System capacity, calculated in available seat miles (ASMs), expanded 10.7% to 1.23 billion in the same month.With traffic growth marginally outpacing capacity expansion, load factor (percentage of seats filled with passengers) registered a mere 20 basis points year-over-year increase to 82%. This Las Vegas-based carrier transported 1.14 billion passengers in May, reflecting an improvement of 11.8% on a year-over-year basis.Although traffic increased on a year-over-year basis in May, the rise in the metric compared unfavorably to the comparable reading a month ago, when traffic was up 12%. Capacity expansion was more in this month compared with 9% in April, giving rise to capacity-overexpansion related fears. The reading for May load factor too compared unfavorably to 83.2% in April.Other HeadwindsApart from capacity-related woes, the stock is still suffering from CBS News' report, 60 Minutes, alleging that it was facing a number of safety-related issues. The damaging television program was aired on Apr 15. The allegations are being investigated.Also, escalating fuel costs are hurting the company’s bottom-line performance. In the first quarter, fuel costs increased in excess of 20% year over year to $2.18 per gallon. The metric has risen further subsequently. While the reading was $2.28 per gallon in April, it increased even higher to $2.44 per gallon in May.With oil prices on an uptrend, it will not be surprising if Allegiant Travel revises its current-year fuel price guidance of $2.20 per barrel upward in the near future.Zacks Rank & Stocks to ConsiderAllegiant Travel has a Zacks Rank #3 (Hold). Some better-ranked stocks in the broader Transportation sector are GATX Corporation GATX, SkyWest Inc. SKYW and Expeditors International of Washington, Inc. EXPD. While GATX and SkyWest carry a Zacks Rank #2 (Buy), Expeditors sports a Zacks Rank #1 (Strong Buy). You can see the complete list of today’s Zacks #1 Rank stocks here.Shares of GATX, SkyWest and Expeditors have rallied in excess of 11%, 47% and 37%, respectively, in a year’s time. The Hottest Tech Mega-Trend of AllLast year, it generated $8 billion in global revenues. By 2020, it's predicted to blast through the roof to $47 billion. Famed investor Mark Cuban says it will produce "the world's first trillionaires," but that should still leave plenty of money for regular investors who make the right trades early.See Zacks' 3 Best Stocks to Play This Trend >> 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 SkyWest, Inc. (SKYW): Free Stock Analysis Report Allegiant Travel Company (ALGT): Free Stock Analysis Report GATX Corporation (GATX): Free Stock Analysis Report Expeditors International of Washington, Inc. (EXPD): Free Stock Analysis Report To read this article on Zacks.com click here. Zacks Investment Research