U.S. airlines received $593.6 million in revenue from fees charged to passengers canceling or changing reservations in the second quarter, according to a U.S. Department of Transportation Bureau of Transportation Statistics report released Tuesday.

That number is up from $553.9 million in the first quarter. Delta Air Lines Inc., which provides service to Des Moines International Airport, received the most fees, $181.8 million.

The next three highest on the list are American Airlines, United Airlines Inc. and US Airways Group Inc., all of which serve Des Moines. Other notables on the list that serve Des Moines were Frontier Airlines Inc., which ranked No. 12 with $4.3 million in revenue, and Allegiant Air, which ranked No. 15 with $1.2 million.