How do I read these Code Churn numbers on TFS 2010 Build Summary Report?

Question

I am using TFS 2010 Team Build and the related reporting services report Build Summary. Within this report is a Code Churn column. However, the data displayed in this column isn't making any sense to me.

In my application I have roughly 10,000 lines of code (it's a fairly new app). However, the code churn gives me a number 57791. Can anyone explain this to me?