Tricky Transpose and Sort

First, thank you for looking and any assistance you can provide with this data problem. I have a very large spreadsheet consisting of thousands of rows. I need to transpose the data from columns to rows, but it needs to also sort the data into month/year categories. This may best be done in two separate steps. I have attached a file with two sheets. One is an example of the raw data and the second is the desired format. Any assistance is greatly appreciated.
Thank you