A Department of Justice memo that detailed interrogation techniques used on prisoners at Guantanamo Bay notes that in August 2002, suspected al-Qaeda official Abu Zubaydah was waterboarded 82 times, while the following March, 9/11 suspect Khalid Sheikh Mohammed was waterboarded 183 times. But as the blog Emptywheel points out, there's no way to get to those numbers within the CIA's guidelines.
If you do the math, the CIA maximum allowance is still less than half of 183 waterboarding sessions. But aside from the arithmetic troubles, Emptywheel points out that the main problem is that a technique that required 183 applications to work is considered an effective means of interrogation.
(Read more waterboarding stories.)