What does "Regularization" mean?

To explain our billing process: in any given month (M), we bill an estimation of the payroll costs upfront and once the payroll has been run by our finance department and we receive the actual amounts, we reconcile any difference (+/-) in the next month (M+1).

The difference (+/-) results in what is called a "Regularization".

An example: Some last-minute changes were made on Sujit's commission and expenses claim, which makes the actual payroll costs higher than what was predicted.

You can view each employee's adjustment amount on a global level - Positive amount means underpayment and negative amount means overpayment.