Both the individual and business master files are still written in IBM mainframe assembly language, and are circa 56 years old. See the table on page 4 of this PDF for a list of the oldest systems in operation:
Number three on the the list is The DoD's Strategic Automated Command and Control System, which runs on "an IBM Series/1 Computer—a 1970s computing system—and uses 8-inch floppy disks". No biggie; it just "coordinates the operational functions of the United States’ nuclear forces, such as intercontinental ballistic missiles, nuclear bombers, and tanker support aircrafts."
> Standard CFOL Access Protocol (SCAP) is written in COBOL/Customer Information Control
System (CICS). SCAP downloads Corporate Files On-Line (CFOL) data from the IBM mainframe at
the Enterprise Computing Center, Martinsburg. The CFOL data resides in a variety of formats
(packed decimal, 7074, DB2, etc.)
never ever under estimate the government and military's ability to keep old systems operational well past what others consider reasonable.
anecdotal, back in the late 80s I was in the USAF. Our secure communication center was running the first model Burroughs machine to not use tubes. It was that old. It could boot from cards, paper tape, or switches. The machine was older than many people who would be assigned to it. This was closely repeated in the main data center (personnel records, inventory, and such) which had a decade old system that migrated off physical cards by 89 but still took them as images off 5.25 floppy uploaded by PC)
