Delta Air Lines shares sold off yesterday as part of a broader downturn across the airline industry, which saw major carriers like United Airlines and American Airlines also experience significant declines. The sector-wide weakness was primarily driven by a rebound in oil prices, which stoked investor concerns regarding rising fuel costs for airlines. This negative sentiment weighed heavily on the industry, causing Delta to pull back alongside peers like JetBlue, which also saw its stock slide amid the same fuel-related pressures.