List subsets are lists that contain a selection of items from a larger list. Reducing cell count and sparsity in a model, list subsets enable reuse of list items. A single list item can belong to multiple list subsets.
To illustrate, say you assign transactions from a transactions list, Transactions, to a list subset, Card Transactions. Card Transactions can then be used as a list in its own right in a module. Only the items assigned to Card Transactions will appear in the module.
Create a list subset
In Lists and Roll-ups > General Lists, open the list that is to be the source of the subset.
Select the Subsets tab and click Insert.
Enter a name for the subset and click OK. The new subset is displayed in the list of subsets.
Select the Grid View tab. A new column, bearing the name of the subset, is displayed,