Returns the serial number of the date before or after a specified number of workdays with custom weekend parameters.
| Name | Type | Description |
| arg1 | any | Is a serial date number that represents the start date. |
| arg2 | any | Is the number of nonweekend and non-holiday days before or after start_date. |
| arg3 | number | Is a number or string specifying when weekends occur. |
| arg4 | any | Is an optional array of one or more serial date numbers to exclude from the working calendar, such as state and federal holidays and floating holidays. |