Use
During activation, you use
Methods to activate all items of the planning template for which the methods have the values True. For the evaluation of the planning template, the R/3 System considers only active items with their objects and quantities.If, therefore, the method uses the value "True" (active) during planning template evaluation, the SAP R/3 System transfers the objects of the rows with the corresponding quantities to planning.
If, during planning template evaluation, the method has the value "False" (inactive), the system ignores these items.
The system evaluates the activation condition before the object selection or quantity determination. This means that you can not evaluate any attributes of the object (e.g. cost element category).
To enter a more complex method, branch to the activation editor.

You can use the following condition to specify that your planning template may only be used on cost center 1100 in the periods 7 to 12 of the current fiscal year "1998".
CURRENT_PERIOD >= '7' AND
CURRENT_FISCAL_YEAR = '1998' AND
COST_CENTER_NAME = '1100'
See also:
Defining Methods