Hofner serial number dating
Notice that there is quite a bit of overlap in numbers and years.
instrument production history, production dates have been applied to various components.
Instead, the instrument's country of origin appears on the decal on the back of the headstock, near the serial number.
This new numbering scheme was short-lived and was replaced only a few months later by an improved scheme that identifies an instrument’s country of origin and year of manufacture in the body of the serial number.
You might consider referring to magazine ( a great and helpful resource for those who buy, sell and trade vintage instruments.
You might also consider consulting one or more of the many instrument dealers who offer appraisals of vintage instruments, such as Elderly Instruments ( Gruhn Guitars ( Mandolin Bros.