I can tell you from first hand experience that getting a warrant TO the FISA court from a sponsoring agency is a massive bureaucratic battle in and of itself.
Reason being, the agency powers that be don't want to send something up that will be disapproved because it takes significant time and effort of general counsel and leadership of these agencies to process, implement and track to maintain compliance - even if the warrant is reasonably broad.
So these numbers really don't mean anything in terms of just "blanket surveillance." The bar for even getting something to the court, in my experience, is incredibly high and you typically need very high ranking people to sign off on it. Which means your evidence, reason for doing and ensuring that it is within the boundaries of EO 12333 and a million other regulations, has to be pretty airtight.
Reason being, the agency powers that be don't want to send something up that will be disapproved because it takes significant time and effort of general counsel and leadership of these agencies to process, implement and track to maintain compliance - even if the warrant is reasonably broad.
So these numbers really don't mean anything in terms of just "blanket surveillance." The bar for even getting something to the court, in my experience, is incredibly high and you typically need very high ranking people to sign off on it. Which means your evidence, reason for doing and ensuring that it is within the boundaries of EO 12333 and a million other regulations, has to be pretty airtight.