I can make custom lists for using to filter data I have but I don’t understand in what situation I would create a new list during a primary and secondary sort?

E.g. in MS help section it suggests a custom list of small, medium and large – but how can that be applied to sort data? Surely you’d have to already have a column of small medium and large???  I am confused!

​I can make custom lists for using to filter data I have but I don’t understand in what situation I would create a new list during a primary and secondary sort?E.g. in MS help section it suggests a custom list of small, medium and large – but how can that be applied to sort data? Surely you’d have to already have a column of small medium and large???  I am confused!  Read More

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