Specifies the order in which the items of a chart are displayed. Valid values are:
- Key - Sort alphabetically by the key value (MapChart) or by the category/key value
(CategoryChart).
- Value - Sort by the numeric value.
- InputOrder - Preserve the order in which the items were defined. If more than one value is
received for a particular key value (MapChart) or categoriy/key value combination (CategoryChart),
the first value received defines the order.
By setting the property sortAscending to false a reverse sorting for each of these options can be
obtained.
Type: Enumeration.