Shares of car rental giant Avis sank 12.5% in after-hours trading as both revenue and earnings per share for the second quarter came in well below analyst estimates. The company blamed shifting booking trends.

Earnings on a generally-accepted accounting basis were 98 cents a share versus the $1.92 analysts had expected. Revenue came in at $2.998 billion, versus the $3.097 billion expected.

"The second quarter demonstrated how we are operating the business differently: as booking trends shifted, we moved quickly to resize fleet, protect utilization and returns, and deliver Adjusted EBITDA in line with our initial expectations," said Brian Choi, Avis Budget Group CEO.

"We remain focused on disciplined execution, stronger customer experiences, and building a business that can perform across different demand environments," Choi said.

Shares fell to $145.50 after closing the regular session up 1.6% at $166.32

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