Do we know the exact print date? [solved]

These notes are listed as 1961, but do we know the exact print date?

This is mine, it has UV activity also:

I do not know of exact printing dates of these notes. They were printed as needed until the design was changed in 1991. The printing method did, however, change to offset, from metallographic (a type of lithographic printing), in the late 1980s.

Thanks!

As far as I can see this is the "sixth issue" so the printing years are 1987-1990.