LAG() Rent Increases without Time Scale
New Model Builder here! I'm working to enhance an older model that uses a hierarchical list as a Custom Time Scale (CTS Months). The list is used in lieu of a time scale for most modules, however one of the enhancements involves applying market rent increases to the next 'time period'. i.e. a 5% market rent increase should not be applied to Month 1, but should apply to all other months.
We have a similar model for budgeting on a calendar year that does not have this custom time scale, and a simple LAG(rent increase,1,rent per unit) works just fine because it has a 'real' time scale. Unfortunately, I can't do that here as the module in question uses the CTS Months list instead of Time:
CTS Months List:
I was able to achieve this with the solution below, but is there a better way?
My solve: creating a separate module with a single line item that has a boolean indicator be true for just Month 1, then applied the formula below to the 'Increased Rent Per Unit line item pictured above: