"averages" for their 13th birthday when it looks like they grow ~ 2" during that year.

For the people too stupid to realize the fallibility of datasets, I work with several large federal datasets as part of my job. I've had to contact them about BIG problems with their data several times. I'm actually currently in the process of trying to get them to correct severe inaccuracies with a forestry dataset right now. The people responsible for creating, publishing, and maintaining these datasets are very frequently morons. But go ahead and pretend that what I said is crazy. I don't talk out of my backside like some people do.

And I didn't say I know the dataset to be wrong, just that I'm not convinced of its accuracy. Given my considerable experience with similar datasets, I have good reason to question its accuracy.