Number on Reverse of Official Duty Token

I'm wondering about the specific numbers on the reverse of the token.  Was each business issued a unique numberfor tracking purposes?  If not, what does the number represent?

According to Atwood Coffee reference these were numbered at the time they were minted. I added the information below to the page.

10,000 minted 1/29/1964 numbered 1 to 9999

5,000 minted 5/10/1968, numbered 10000 to 14999

10,000 minted 9/28/1972. Reference (AC) does not mention these being numbered.

Holy cow. Thanks!