Im having a bit of a headache with conceptually understanding how to achieve an end goal.
I have attached a workbook which lists the progress so far.
It is essentially 'as of date' analysis
I wish to establish what the Volume Booked to travel on the Travel Equiv Date PY1 (D) was at equivalent points in time in history (E).
These points in time in history are based upon a calculation of selected Travel dates (A) and the max(Booking Date) of each of those dates (B).
I have tried several appraoches and feel that the manipulation must be made within the P() part of the expression associated with [Booking Date] but can not nail the syntax.
Any help would be greatly appreciated.