Reporting Services: Adding conditional visibility to rows with repeating values

Recently I was developing a Matrix layout report where the row headers repeated for a given value, but the user only wanted to see the first occurrance of each unique row heading value and leave the other row headings blank until the next new value.  In a tabular layout, I might have just added a new Group based upon the repeated value and displayed the heading above the set of related rows.  However, for a matrix report, that gets a bit too complicated due to the behavior of dynamic row headers and grouping, so I settled on dynamically changing the Visibility.Hidden propery based upon the following expression:

=Previous(Fields!Col1.Value) = Fields!Col1.Value

Enjoy!

See Also:
Previous Function