Hi Harish,
Yes, you can do something like that. There is actually only a single Time Spent system attribute and it is used for an internal calculation based on how you want Progress represented. If you choose to see Progress based on Time Spent, then Time Spent is calculated as Estimate - Time Remaining (which is actually the name of the attribute on the Task as far as I remember). This result is not stored anymore. Conversely, if you want to see Progress based on Time Remaining, then that is calculated as Estimate - Time Spent using the same Task attributes.

In any case, you can add a custom attribute to the Task if you like and then add a Calculated Value for that attribute which can be implemented as Java Script. You would specify this in the Eclipse client:

1. Open the Project Area
2. Click on the Process Configuration tab
3. Navigate to Project Configuration > Configuration Data > Work Items > Attribute Customization

You'll find other examples of this by looking at some of the attributes we already have that do this, such as the WSJF attribute.

Hope that helps,

Amy