The NSA is recording every call in the Bahamas and Afghanistan. They can listen to any call made in the last 30 days. (Edit: Only cell phone calls, but still.) It's possible that a similar rolling-window system is in place for calls going through the USA.
Bahamas: https://firstlook.org/theintercept/article/2014/05/19/data-p...
Afghanistan: https://wikileaks.org/WikiLeaks-statement-on-the-mass.html