Hello,
World Coins, and Schön, indicate a year 1972 (1392) for this coin, supposedly struck at 1.5 million copies.
This year is not on the Numista sheet of this coin, and after research on the net, I have not found any information. So I guess it simply doesn't exist, but I would like to have confirmation.
If it's a deliberate act to remove this year of Numista sheet, it would be interesting (especially important) noted in the comments that same sheet, just to inform, and also to avoid that one day he will be added if it does actually not exist.
The "Comment field" on the sheets is too little used, while it has important, and this on all the catalog!