Management reporter to Sharepoint problem

I've followed this tutorial: community.dynamics.com/.../how-to-publish-management-reporter-reports-to-sharepoint.aspx

The reports work just fine; however, every time I generate a report for any period it replaces the previous one.

For example, I title the output name as "Jan2013" for period 1. I generate the report and it publishes it to sharepoint.

Next, I select period 2 and title the output name as "Feb2013". It generates the report and publishes it to the same document library as Jan2013. So now I have two reports published on Sharepoint titled Feb2013 and Jan2013.

Here is the problem. When I click on Jan2013, via the document library in sharepoint, it shows all the information for Feb2013.  

Further illustrating, if I select period 3, title the output name as "March2013", and than generate the report it replaces Jan2013 and Feb2013, in sharepoint, with March2013 information. The Jan2013 and Feb2013 titles are retained but the actual report information is changed.  

How do I get it to stop overwriting previously generated reports? I thought naming the output name would do the trick but obviously it doesn't.