Creating Planning Calendars without Calculation Rule 

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       1.      Proceed as described in Creating Planning Calendars with Calculation Rule under points 1 to 7.

       2.      Choose  Periods.

       3.      Enter the start and end dates as well as the name of the periods.

If you enter only start dates, the finish dates are automatically calculated by the system (except for the last finish date).

       4.      Save your entries.