They have outlier models, but look at the probabilities associated with them (should be >90%, i.e., <10% probability for those lines). A better statement on my

They have outlier models, but look at the probabilities associated with them (should be >90%, i.e., <10% probability for those lines). A better statement on my behalf would have been that their probabilistic distributions have been historically very accurate. They are also updated very diligently to account for new phenomena. I don't work for the UN, but they take population growth very seriously.