Some bonus payments will be accrued across the whole year, but if you wish to apply a percentage bonus in just one month (or a selection of months), this is how to do it.
This will not be created in our HR Formulas but as a Pay Raise. Because our pay raises may be applied to individual months, you can apply the percentage bonus to a particular month.
For example - each employee will receive a Holiday bonus of 5% of their salary which you wish to budget for in December.
Go to Employees > Manage Payroll, check the box at the top left to select all employees, then hit the Grow button at the top right and fill in the form as below, selecting only December in the Periods menu.