U.S. airline bookings slipped 2.3% in May from a month earlier, the second consecutive monthly drop this year, while fares soared over 2019 levels, according to an Adobe report published Tuesday.

Consumers spent $8.3 billion on domestic tickets last month, up 6.2% from April.

So far this year, consumers spent more than $37 billion for domestic flights, almost double what they spent in the first five months of last year, when Covid-19 vaccines were just becoming widely available.

“While some consumers have been able to stomach the higher fares, especially for those who delayed travel plans during the pandemic, the dip in bookings shows that some are rethinking their appetite for getting on a plane,” Vivek Pandya, lead analyst at Adobe Digital Insights, wrote in the report.

Airfare has surged thanks to high fuel prices, labor shortages and red-hot travel demand after two years of the pandemic, marking one of the most dramatic examples of rising inflation this year.