When I use the ruler on GE and run it from North to South I get one heading but when making the exact same line from South to North I get a different heading. For instance, when I measure from the Empire State Building to Cape Canaveral Air Force Station it reads 205.83. But when I measure from Cap C back up to the Empire S B it reads 22.6. If it's 205 deg one way it should be 25 deg the other way. Would anyone know why?