1916
Gold window already shut
In 1916 the classical gold window has been closed since 1914. It is not rebuilt. Britain’s return to a pre-war parity is 1925.

In 1914 war finance suspended convertibility and gold shipment. That peacetime order has not been restored.
The Federal Reserve already exists. Britain’s return to the pre-war sterling parity is 1925. The Genoa sketch of a gold-exchange system is 1922. Neither has happened.