Item-To-Add
When a value is assigned to this property, a new item is added to the list.
Multiple values can be added at the same time, enclosed between parentheses.
The position of the new item can be controlled with the Insertion-Index property, provided that the List-Box control has the Unsorted style set.
The value assigned to the property is split into columns according to the value set in the Data-Columns property. The values of all the columns are set simultaneously.
 
Example - Modify a list-box to insert a new item at the bottom of the list
procedure division.
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  modify screen-1-lb-1 item-to-add "new item"
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