Subtraction of data and transfer to other sheets

[lmtzprog]

I'm hoping to use a macro that first allow me to subtract one month data of a particular year to another and then transfer the results to another sheet. For example, subtract January 2001 to January 2000, February 2001 to February 2000, January 2005 to January 2004, February 2005 to February 2004, and so on. I can do it manually but it is excessively time consuming.

I attached an example of what I'm trying to do if I didn't expressed myself to well.

Thanks in advance!!

Lmtzprog