According to EPIC, the first public reporting on National Security Letters has been released, showing over twelve thousand NSLs were issued in 2006.
FISA Orders Up, Government Reporting on National Security Letters Begins. According to the 2007 FISA report (broken link), the Foreign Intelligence Surveillance Court approved 2,370 application to conduct electronic surveillance and physical searches in the United States in 2007, up from 2,176 applications approved in 2006. For the first time, the report includes information regarding the total number of requests made by the Department of Justice with National Security Letter authority for information concerning U.S. persons. in 2006, the government made approximately 12,583 NSL requests for information concerning 4,790 U.S. persons. The 2007 NSL statistics are expected later this year. (May 1)