Custom variable in Crystal Report

VS 2005 : Crystal Report

I have a variable : Compliance

In which i wrote the syntax as follows ..

{DrugTable.Compliance} + "%"

Based on the above, i get output as ..

10.0% N/A%

10.0 or N/A is picked from DrugTable.

I am trying to write If condition ..

If {DrugTable.Compliance} <> 'N/A'
{DrugTable.Compliance} + "%"
Else {DrugTable.Compliance} = 'N/A'
{DrugTable.Compliance} 开发者_StackOverflow中文版

I am facing Syntax Error on my above Syntax !!

Assuming field is a string:

IIf({DrugTable.Compliance}='N/A', {DrugTable.Compliance}, {DrugTable.Compliance} + '%')