Customizing the metamodel : Keywords for USRPROPS : LEGEND
  
LEGEND
The string of the displayable property in a rectangular symbol which overrides the property name.
Example
PROPERTY "Description"
{ EDIT ListOf Data
DISPLAY { FORMAT Key LEGEND "Key data" }
}
Syntax
LEGEND "<Your Text>"
Whatever text you place in the quotation marks will be displayed on the symbol above the entry, only if there is a value for the entry.
LEGEND ""
Displays a straight line without any words, only if there is a value for the entry.
LEGEND "$$FORCE$$"
Displays a horizontal line above the entry on the symbol. This line acts as a divider. The "$$FORCE$$" keyword is different than simply using " ", in that it forces display of a horizontal line even if the property display is suppressed through the display mode dialog.
LEGEND "$$NONE$$"
Does not display a horizontal line above the entry on the symbol, whether or not there are values for the entry. This line normally acts as a divider.
LEGEND "$$VFORCE$$"
Enables you lay out properties from left to right inside symbols, and draws vertical lines between them. See VFORCE keyword.
LEGEND "$$VNONE$$"
Enables you to lay out properties from left to right, but does not provide a dividing line.