Under the "Period" tab there is a sub-tab called "New Suppliers", here we have created an easy to read table that shows you month on month how many new suppliers you have raised POs with and for how much. You can use the date selections highlighted below to narrow down to view by certain months or years. 

Within the table you can select suppliers to add them to your filters, this will stay selected as you navigate around the tool.

As with the rest of PD you can right-click and export the table to excel.