Do you want to know the overall conversion rate of your sales funnel? This can easily be done in Zoho Reports with a few clicks. 

The funnel chart in general, will show the progressive conversion rate of each stage, using the  Show Convertion Rate option in  Charts Settings. Zoho Reports enables you to calculate the overall conversion rate by comparing the first stage and the last stage in the funnel.

The below gif shows how to add the conversion rate to your funnel chart.