Ivan Popek has been spending a lot of time lately digging into TFS 11.  He has written a series of posts on the APIs for teams in TFS 11, and he explains the burn down chart trend lines.

• TFS11 API: Query Teams and Team Members

• TFS11 API: Reading the Team Configuration – Iterations and Areas

• TFS11 API: Managing the Team Iteration Schedule

• TFS11 API: Managing Team Administrators

• TFS11 API: Customizing the Process Configuration

• Understanding how the Team WebAccess burndown chart works, Part 1

• Understanding how the Team WebAccess burndown chart works, Part 2

• Understanding how the Team WebAccess burndown chart works, Part 3

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