Selectively tally rows from a module based on '(column name) IS x', or similar
I'm trying to write a formula in the module 'Spend (FY18)', that refers 'Budget (FY18)'. I want the formula to check the column 'Period' (which is a pick-list of four options) and if that period equals Q1, it will take the £amount from that row, and add all such rows together to give a £total for that Quarter (repeat for Q2, Q3, Q4). I've tried a few approaches, but something isn't quite falling into place. Apologies if this Q&A exists; I've struggled with the technical term for what I'm asking - Thanks in advance!