Determining the Difference in Months between Compensation Plan Start Date and a Event Date

Hello,

I need to compare the start date of the compensation plan (component) with a specific date.

I need to calculate the difference between the start date of the component's compensation plan and the event date from the transaction.

The return value should be in months based on the period.

So, how do I use the start date from the component plan as an input parameter?

And what is the syntax of the expression?