Team web access has some useful built-in reports that can't be customized. However, these reports do not depend on the SQL Reporting service, and reports are available on Visual Studio Online too. The next section explains available standard reports in team web access.
The velocity report is used to forecast backlog accomplishment per sprint. This report shows the number of finished and scheduled backlog items across sprints/iterations. This report can be found in the top-right section of the backlog page and helps with forecast and release planning of the project.