If you are using also the TFS Build feature you can use a standard
report to view the code churn: Build Quality Indicators.
If you are not using TFS Build then you can use this guide to
get that information:
The guide is presuming that you want a filter based on the Build
Definition but you do not have to use that. You can use a Changeset ID
as a report filter and get all the details that you need regarding the
code churn.
Taken from here.