Project Online custom report

Hi all,

We have created a planning in Project Online, our planning is for a long project with a lot of diferents tasks. Then we need to monitor the tasks in detail.

I have already conect with the data, and i can read the values of % and de %planned, but % completed is a temporal value in that moment i would like to record when someone upload the value of the % completed  to be able to graph how is going the project.

It is possible? 

 Thanks!

Anxo