Hi! I have a large activity table and am confused how to calculate the difference between current line timestamp and prior line timestamp. example: line 2 timestamp - line 1 timestamp, then line 3-line 2, etc through all the steps of the case

I can do this in the PQL with a lag function but was advised to look into this from a Celonis calculation. Is there a particular function I should be looking at or a way to do this? While the case explorer, this seems to be done automatically, but I cannot figure a way to do this within a dashboard. Thanks!