Wheel Alignment question for smart people

[Plasnart]

Ok mate this is what I worked out. If you look at your wheel from above and turn it 360 degrees with a pen taped to the tread, you'll draw a circle on the floor. This circle will have a diameter of 818mm. You want to work out the length of that circumference for a 2 degree turn. So the circumference of a circle formula is 2 x pi x radius. So your circle is 2 x pi x 414 = 2601.24mm in length. So for every 1 degree slice of that pie, the circumference is 2601.24/360 = 7.23mm. Therefore for a 2 degree toe in, 7.23mm x 2 = 14.46mm. This sounds like wayyyy too much toe in mate, unless I've completely stuffed up the calculation!