OPTE and how is it determining the Wisconsin tax bracket for the supplemental rate

Summary:

We are testing OPTE and have Wisconsin employees with the same amount of taxable income but different rates. Is there an explanation of how the system is determining the flat rate for supplemental pay calculations?

Content (please ensure you mask any confidential information):

Is the difference in the rates being used based upon the estimated annualized income? We can't determine how the rate is selected by OPTE.

Version (include the version you are using, if applicable):

26A

Code Snippet (add any code snippets that support your topic, if applicable):