Formulas with Mirror Columns

Hi everyone,

I have a high level team board, with all team members and their goals for the year. So in this board we have a goal per person of 120,000 GBP to reach. This is based off projects they are connected to, and each project has a cost which will add to the goals of the people working on it.
Team Board:

Project Costs is a mirror column coming from the connection to the projects, and Remaining is the formula column which subtracts the project cost from the capactiy cost. This works when one project is linked.

When I link another project to the team member, the formula shows an error. The Project cost will sum all items to 1300, but the formula doesn’t calculate 1300 away from 120,000.

Can anyone please tell me why this would be? Can we not use mirror columns in formulas?


Hi @shaunafitzgoo - I suspect the two projects connected are from different boards? If this is the case you formula columns do not support calculations from multi-board mirrors.

This is one of the reasons why we try to accumulate task level data from multiple project boards into a single “task tracker”. This allows for ease in reporting within overviews and dashboards without hitting these types of limitations.

If you are ever looking for further assistance in overall design feel free to reach out any time.

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I just saw this. If your mirror is a single level, i.e., mirroring a number column, and not a mirror of a mirror, you can copy the mirror value to a local number column using Column Magic. Then you could use that column in your formula. If it IS multi-level, “a mirror of a mirror… of a number”, that should be available in about 2 weeks.

Jim - The Monday Man
:magic_wand: Column Magic :sparkles:- the magical columns toolbox app