That's a difficult question to answer - If we go by social media, I'd be inclined to believe it was somewhere around 0.0000!%. However, social media is a hotbed for toxic, narcissistic and downright idiotic people who'll do anything for attention. In the real world, the number would be a lot higher because for every distinguished genius like Steven Hawking, you'll have thousands who aren't aware or haven't been recognized as such. Another thing to factor in is what do we define as geniuses? Is it based on what they've contributed to society using said intellect? How much information they can retain and regurgitate about things such as real world issues or is it something else entirely?