Payroll: 16 salaries in the year

Hello;
If we have 16 salaries in the year (16 months), so there is one salary each the mid of March, Jun, Sep and Dec of every year, how this can be managed in the HR payroll?

Is it possible to use the condition to check if the date is 15th of March or 15th of Jun or 15th of Sep or 15th of Dec then to include the value in the formula (and the value in the formula will be the addition for all the components)? If it is possible to use the condition in this way, it will be wonderful.

Thanks for the help in advance.

Regards
Bilal

In the Salary Slips, you can define From Date and To Date as well. But for same dates, you cannot create another Salary Slip. Perhaps you should use other transaction like Purchase Invoice or Journal Entry for additional payment.