Indy tells Army Intelligence that what matters is the length of the staff, the spot in the room and the time of day. He doesn't mention the day of the year. So the different spots on the floor are for different days of the year. Belloq did his calculations about a day before. Now, that means Indy's hole should be basically the next one over, if any, but suspension of disbelief.
A real kadam is 11.5". However in the universe of Raiders it's 14".
Sallah said it was about 72 inches, but he was wrong. Indy knew a Kadam is actually about 14". Thus the staff is about 7 feet tall.
The original script has different numbers, and adding not subtracting, with the staff being 82.5" tall, which is close-ish to what we see, and what the prop makers would have been going by, I expect.