Automate time calculations

Automate time calculations

I have in many of my forms time fields that calculate the difference between currenttime and a set time:
( ((ETB - zoho.currenttime)  /  (1000  *  60  *  60)).round(1) ) 

This works fine when updating and editing the record. However I often work in a report overview, and I need to find a way to re-trigger the calculations for all the records in order to get updated time difference on regular intervals i.e. every 2 hrs, I have however not been able to figure out a way to do so yet.

Any ideas?