I would like to be able to set milestones based on the sum of a group accounts. In Projection Lab, Australian concessional and non-concessional super are modelled as separate accounts, but in reality they are the same account. This leaves the problem of not being able to set a milestone when my total super reaches a certain point.

Similarly I would like to set a milestone when the total of my wife and my super accounts reach a certain milestone. This would allow that to happen.

Might be useful supporting other arithmetic operations (plus, minus, times, divide) to allow other unknown purposes?