"Stop at Target" for percentage based savings goals

It would be great to have an option to stop assigning to a savings goal (that is some percentage of an account) once it’s reached, and then any other funds get allocated to other goals in the account.

Right now, I could have a 5k goal set to 50% of an account, but if that account grows unexpectedly large I could have 10k+ assigned to my 5k goal which I may not need or want.