[Urgent] Get growth by when having running-difference

[clingst]

May I have your advice how can I get the growth % with Running-Difference?

I am working on a relational package.
By using Filter, i extraction the revenue on 201412 and 201507.
By using running-difference, I got the difference between the two months.

running-difference ([Revenue] for [Application Type], [Branch])

However I cant figure out how can I get the growth since I cant determine the BASE (which is the revenue in 201412) from a relational package.

I want to avoid creating another query which is just to retrieve the 201412 revenue and then later on join to my working query for the Base purpose.
Please advice..

[Lynn]

You can create a query item for base that uses a case statement to pick up the revenue if the month is 201412 or else 0 for any other month.