I am at 4500' above sealevel.

Water boils at 203.4 F degrees as opposed to 212 F which is just under 8 degrees of the sealevel index. I am having a hell of a time calibrating a new thermometer and I think I know the answer to this, but since water boils at 203.4 degrees, are rest of the increments of the thermometer affected as well? Thats a great deal of difference when you are mixing air/fuel, and means the difference between winning and loosing, or more importantly, the difference between extracting an award winning malt sugar suitable for brewing, or a so-so malt sugar.

If the boiling point is off by 7.6 degrees, does that hrow everything else on the scale off as well???