Our algorithm states that the ratio should be around 5, meaning if you follow 200 people, you should have 1000 followers. Which would explain why you keep saying that box.
Our profile checker is our opinionated view of how a profile should be. What you do with those results is completely up to you. It seems to me like it's safe for you to ignore that stat, since you're satisfied with the ratio you currently have (and you should, it's excellent).