What percent of people have only one good eye
Almost everyone has one eye that is slightly stronger than the other. Perfectly normal. (If you mean missing an eye - more common than you can imagine - cancer, accidents & war injuries can cause eye loss.)
I have only one good eye but I'm not sure what the percent of people that have only one good eye is so...sorry.
Google it up and you'll find the estimation of percent of people who have only one good eye.
maybe 1 of 1000
It depends on what you consider to be a "good" eye.