"Overweight" is a subjective term. There are quite a few scales for measuring the "average" or "perfect" weight a person should be and because of all the variables, like gender, height, body type, age, etc., there is a tolerance range that isn't always correctly labelled on your weight charts.
You must also take into account, the different body types, below is an example image showing three body types, an "*********" body type can look overweight when compared to a "ectomorph" body type of the same height and they can both be extremely healthy.