If my readings from my CoCo gauge and my Davis VP2 were off by only .01 or .02, I would tear down the goal posts in celebration. I have two VP2s, a CoCo gauge and a Rainwise 111 and one day last week my CoCo gauge showed .30, the Rainwise .28, VP2a ..24 and VP2b .18! My differences are not right and being off .01 or .02 I wouldn't worry about it! All four gauges are close to each other and about the same height from the ground.