In the second half of 2016,Girlfriend Who is Crazy About Big Things Apple dealt with government data requests affecting more than 20,000 devices -- nearly double from what the company dealt with in the first half of the year.

Also, for the first time ever, Apple reported receiving a National Security Letter (NSL) in its latest biannual transparency report.

NSLs are demands from the FBI for user data -- normally, they're subject to a gag order, but they're declassified once a case becomes inactive. Apple didn't reveal the contents of the letter, only that it received one.

It's not uncommon for large tech companies to get NSLs. Last year, Google published eight of the letters it received from 2010 to 2015.

Also revealed in the report was a decline in the total number of device-related requests for data from U.S. government agencies, from 4,822 in the first half of 2016 to 4,254 in the second.

Yet the number of devices affected by those requests nearly doubled from 10,260 to 20,013.

Mashablereached out to Apple for an explanation for the increase.