PERFORMANCE PERCENT COMPLETE ENCOUNTER PROBLEM

To all co-Planners,

I have an unexpeted encounter probs:

Facts:

I am using P6.1 stand alone.

Resource loaded and cost loaded (manpower in 0 price/unit and cost in lump sum 1 price/unit).

Using the project as base line.

Duration type: Fixed duration and units

Complete % type: Duration

Problem: 

When i update, activity with 100% complete will give the earned value as 100%.. But for activity with less 100% complete will give any no performance% complete which means that there is no earned value.

Hope that you can give me hands on this one.. thanks..