Create Macro to Add Rows when the # of rows vary each month

Hi,

I am trying to create a macro that will do some formatting and one of the things I would like to do is for the macro to add up several different columns. The thing is the number of rows will vary from month to month and I would like totals to be just underneath the last row. What's the best way to do this?

I have attached a sample of my document.

Thanks for the help.