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On the form, there are two required fields: Description and Type (Accrual or Deduction). 
The "Accrual (Deduction) Type (create)" form
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In the Formula field, you can create a formula for new accrual or deduction type (refer to the Creating a formula section below).
Creating a formula
You can create a formula for calculating the accrual or deduction amounts of the type if you click 
button next to the Formula field (available if the Has a Base check box is cleared). This opens the Edit Calculation Formula form.
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You can enter mathematical operations (addition, deduction, multiplication, division) manually from the keyboard. If you need new parameters (not listed in the table), use the Calculation Parameters form to define them. 
The Edit Calculation Formula form
To add a parameter to the formula, double-click it in the list of parameters:
- Fixed Amount: The amount that is specified in the Employment contract as the salary, in-office meals, and so forth.
- DaysWorked: The number of days the employee worked during the month; this value will be available from the database (the documents of Time Sheet type).
- HoursWorked: The number of hours the employee actually worked; this value will be available from the database (the documents of Time Sheet type).
- HoursWorkedbyJob: The number of hours the employee actually worked for a particular job; this value will be available from the database (the documents of Job Order type).
- NormDays: The number of work days in the month according to the calendar.
- NormDaysbySchedule: The number of working days in the month by work schedule which is assigned to this employee.
- OvertimeHours: The number of overtime hours in the month worked by the employee according to Time Sheet.
- SalesAmount: The amount of sales made by the employee; according to the database data.
- SalesMargin: The margin on sales made by the employee.
- TariffRate: The salary (per month); for PaymentbyJobs, it will stand for the standard pay per hour.
Click OK to save the formula.
Defining a base
With the Has a Base option selected, you can define the new accrual or deduction type as based on another accrual or deduction type. 
The "Accrual (Deduction) Type (create)" form with the Has a Base option selected
In the Base Accruals (Deductions) table, select the accrual and deduction types to used as the base and specify a rate for each type in the Rate column. For instance, to calculate vacation pay you may need to use the Basic Salary accrual type.
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The toolbar buttons
Click Save to save the accrual or deduction type or the changes to the existing type or Save and close to save and close the form.
To view or replace the default GL accounts assigned to this accrual or deduction type, click the Edit GL Accounts button (for more details, refer to Adding an Accrual or Deduction Type. GL Accounts).
For description of other buttons, refer to List toolbar.