All-time total download and subscriber counts for iTunes U

Hi! I have a collection on iTunes U, and while the weekly reports are very useful, they only provide information for the stats for that week.

I need to find out how many total all time downloads and subscribers we have (I only need this number once - I can add the weekly total to that afterwards).

So my question is basically how do I find the number of total downloads and total subscribers we have for our collection since its inception.

Thanks!

Sarah