You can use Visual Basic functions to evaluate an input value and return another value depending on the result.
The following expression also returns one of three values based on the value of PctComplete, but uses the Switch function instead, which returns the value associated with the first expression in a series that evaluates to true:
=Switch(Fields!PctComplete.Value >= .8, "Green", Fields!PctComplete.Value >= .5, "Amber", Fields!PctComplete.Value < .5, "Red")

This code is usefull for me. It is working properly. Instead of case statement we can use switch statement.
Thanks a lot.....,
K.Jayasabari