Click 'Reports' next to Activity Menu button
The report window will open up
Click 'Capital Gains' category on left hand side
Click 'Transaction wise - Debt Mutual Fund' icon on right hand side
This report will open without indexation.
Now, Click Customisation button on left and select 'Calculate Capital Gains with Indexation' and click 'OK'
You can compare both the reports, with indexation and without indexation and decide which option is best for you.