How to turn off inconsistent calculated column formula for a column in a table

I have just discovered tables, which I like very much. However, I have several columns where the input is mixed. I have a formula that references a pivot table, which I've copied down the whole column, but not all the entries are found in the pivot table, so sometimes I overwrite them with a text description. This gives me the inconsistent formula message.

Generally I find this feature useful, but I would like to turn it off for this column. Can I do that?

Thanks - Helen