Interesting CRH Find.

I think it's time for a break from crh.....

1989 was the last year of the hand-punched mint-marks on US coins.
Hand punching of mintmarks on proof dies ended in 1985.
After that they started phasing them out on the business strike coins/denominations.
They were completely switched over by 1990 and the cents were the last denomination to have hand punched mintmarks.

1989 and earlier, it isn't in the same place from die to die, but as said, unless it's in the date or somewhere completely out of place, it's no added value although a collector interested in identifiable die pairs might pay a little more than a cent for it.