Your Team Project's reports are made available on its associated Report Portal which is implemented by Microsoft SQL Server Reporting Services.
The information used to generate these reports is obtained from the data stored about your project in the data tier of Team Foundation Server. Much of this information is gathered automatically as your team go about their business, for example when source code is checked into Team Foundation Version Control it is analyzed to determine how many lines of code have changed and this is used to generate statistics on 'code churn'. Other information is gathered more explicitly, for example when a team member enters information about Work Item, or adds a comment about a Team Build.
The types of report available to your team depends upon the Process Template used to create their Team Project. Some of the standard reports created for MSF for Agile template as listed below: