Total above ground gold holdings is not a well-known figure. Some of the Central Bank gold is bogus paper backed by "Deep Storage Gold" receipts, which could be as tenuous as forward sales from miners of gold reserves still in the ground. Private gold stashes are routinely under-reported (or simple lies) to avoid taxes and other unwanted criminal attention. Huge stashes have been lost (and found), 'disappeared' and 'reappeared' in wars, pirate raids etc over the centuries. The agreed upon figure in economics, markets, monetary studies literature going back decades is gold's inflation rate over long terms is very stable around 2.25-2.5%