system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: The significance of the gold in Fort Knox.

What would happen if it was stolen/disappeared? Is it ever used for transactions? Is gold ever added/removed to the current amount held in the vault?
gpt
More interesting is the Federal Reserve Bank of New York, which has almost twice as much gold.  Much of it is owned by other nations.  

However, it seems impractical for other nations to actually withdraw their gold.  What goes on in a transaction seems to be moving gold bars from one nation's shelf to another nation's shelf.