Let’s say you have a number of different Door families in your project, and you want to determine the percentage of the total number of Doors that are Family 1, Family 2 etc, and then you want to show this in your Door Schedule.  First, sort by Family and untick ‘Itemize every instance…’, then use the process shown below.

In this workaround, a Calculated Value is added to be used as a ‘constant’ (it doesn’t really matter what number is used here).  Then, another Percentage calculated value is created against that constant…

Count to grand total ratio in a schedule
Here is how you can do it.
1. Define a formula calculated value: Name – Workaround, Type – Number, Formula – 1.0; Hide the column showing this value
2. Define a percentage calculated value for Workaround.Leonid Raiz

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Count to grand total ratio in a schedule – AUGI