Problem: Vacation given to employees are 60 days per year. How the vacation days will be calculated and how it
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affects the payout.
Solution: If the annual vacation days should be increased/decreased it can be done by creating new vacation type in Master Data and adding it in Employment Contract/Employment Contract Change documents.
1) . In HR&Payroll go to Vacation Types:
2. Instead of creating a new type, you can use Copy option to copy the existing vacation type, give a new description and put needful days per year.Accrual
Accrual Type (for vacation pay calculation) can be left the same as for the previous vacation type if payment settings are not to be changed: 
More about Vacation type creation you can read on the link: 10.1.6.1. Adding a Vacation Type
2) . Go to Employment Contract of the Employee and add new Vacation Type in Vacation type of the Contract: 
3) . Monthly calculation of vacation days and vacation pay will be done by formulas:
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More about Vacation calculation you can read on the link: 10.4.1.2. Creating a Vacation. The Main Vacation tab
4) . If the Annual Vacation days should be increased for the employee who is already working in the company, it can be done by creating additional vacation type and adding it in Employment Contract Contract Change document. Create
Create new vacation type, disable Main Vacation option (since only 1 main vacation can be added in the contract) and put the days' quantity that should be added to existing annual vacation days:
5) . Employment Contract Change document with Change of Pay Type, the changes will be started from the date specified in As Of field:
Add new vacation type in Vacation Tab:
6) . On the next Calculation of Accumulated Vacation Pay after Employment Contract Change entry, the Additional vacation days balance will be calculated started from Employment Date: 
7) . For this type of Vacation, Additional Vacation option should be enabled in Vacation document and data should be filled in Additional Vacation Tab:
More about Additional Vacation you can read on the link: 10.4.1.4. Creating a Vacation. The Additional Vacations tab
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# annual leave 60 days per year