A function in Google Data Studio that calculates percentage of sessions from a particular source
I wish to have the percentage of sessions from facebook.com to overall sessions and demonstrate it in Google Data Studio. I can show the Facebook trend and compares it to overall by adding a calculated field as follows:
CASE WHEN Source = 'facebook.com' THEN 'Facebook' ELSE 'overall' END
But I couldn't figure out how to have a calculated filed that shows the percentage of Facebook sessions Is there a way to day? Any guidance is appreciated.