Modeling Question - How to Create a Toggle between making R&D an Expense and Capitalizing It

Here's what I'm thinking for a quick model approach:

• Create R&D waterfall; R&D for that period/5 (or whatever arbitrary number to capitalize the asset) -Create a toggle that adds back the figure above into EBITDA if capitalizing R&D

Can someone let me know if this is the right way to approach this and if you have a better way to approach this?

Thanks!