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There are four required fields on this form: Description, Vacation Days a Year, Accrual Type, and Calculation Type. 
The "Vacation Types (create)" form. The Main tab
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In the Calculation Type field, you must select a calculation method from the following two options:
- By Base Accruals: The vacation pay per day is calculated based on the accrual type selected for this vacation type. According to employment contract and its changes, the amounts of accruals specified in these documents (and included in the base accruals list for the vacation) are used for calculation.
- By Average Earning: Calculation is based on the average daily amount calculated based on actual earnings during the specified number of months. Selecting this method enables the Number of Months for Averaging field where you can enter the number of months required for averaging. Notice that only earnings based on the vacation accrual type and included in the employee contract (and its changes) can be used.
Click the Save button to save the new record or the Save and close button to save the record and close the form.