Thank you for the response!

I tried hiding the indicator when value is "n/a" , but wasn't able to display the text "n/a" then.

So the way I made it work is ,

1. add 3 images - red , green and N/A to the report

2. then drag and drop Image into the textbox where I want the indicator

3. In the image properties , set the image source as Embedded and the set the image properties based on the condition.