Pivot table cannot find difference between January current year to December of previous year. Excel 2010

Question

I am weeks into making my first ever pivot tables, cant believe the power of them but have hit a snag I cannot overcome.

I have a worksheet which has a column with r

Answer 1

Have you tried combining the month and year in one cell? So on the source data, in the month column have:

Aug-14 Sep-14 Oct-14 Nov-14 Dec-14 Jan-15

Instead of having one column for month name and one for year. Make sure that once you input the months in your raw data tab, they go to the right side of the cell meaning that Excel sees them as dates not text.