How to use current period in Allocations

Summary

We want to use current period instead of an run-time variable

Content

Hi 

We would like to us the current period instead of a run-time variable.
I have seen Abhijit's remark
You should create the variable from Tools>Variable and use it in your rule. Once you schedule the rule from ESS the accounting period will be auto-incremented every period.

But I am not sure of the steps. Can you assist please ?

Thanks
Thien

Version

20D