Summarize/subtotal large excel sheet

[mdrew9]

I have a large excel cash flow that goes for 5 years and has 1000s of rows, I need to report this data in many ways. I attempted to have this as a table then on another tab have a pivot table which summarized the data with the rows I need and all the columns/dates above. Excel doesn't seem to like this.
Have:
Jan Feb
Arron Blue
Arron Yellow

Want (on a seperate worksheet)
Jan Feb
Arron

 

[mdrew9]

Solved! I created a pivottable off of my source table, then created calculated fields ie, 2011 - (Jan - Dec).