While, I was going through chapter 7. Project Cost Management from PMBOK,4th edition.
 
I was wondering whether for 7.3 Control Cost process, Cost Performance Baseline (an output from Determine Budget process) is necessary as an input or not. I think it should be required as an input because PM needs to be able to check against the cost baseline,so that he can ensure that his project is spending too much or spending less than expected.
 
 
Please let me know if my thinking is wrong..