US office vacancies rose to a five- year high in the third quarter, as job losses deepened and employers abandoned space in the recession, property research firm Reis Inc said.

Vacancies climbed to 16.5% from 13.7% in the year since Lehman Brothers Holdings Inc. filed for bankruptcy, New York-based Reis said in a report. Effective rents, the amount actually paid by tenants, fell 8.5%, the biggest year-over-year drop since 1995.