One step further than using the index is to use the unique id of each item in the rg (assuming they are all “things”).
This helps with pagination since bubble treats each page as having the same indices. It also protects you against item deletion/reorganisation, as in those cases bubble would incorrectly move your active conditionals to another item.
Create a state on a parent element that holds ids of lines you wish to be affected. However, if you are actually changing the values of each thing in the db, you should be able to trigger conditionals from that alone.