Or maybe it's just a statistical artifact. Shift a few accidents from
December to January, and shift a few others from next January to this
December, and you have a banner year for airplane crashes caused simply
by the artificial boundaries of the sample set.

Sometimes random events cluster for no reason. In fact, it is highly
unlikely that they would =not= cluster.

Jose

True. From this post and others, I can see that you have a background in
the science of probability, since you are suggesting that the YOY changes
may not be statistically relevant.

I haven't yet read the new Nall report, but I did notice that it is based
upon estimated number of hours flown, per the FAA. No one (here) seems to
question or even want to see the assumptions on the number of hours flown.
Do you know how this number is estimated?

What is curious to me is that when I previously posted the data (from BTS)
about aviation subsidies (by sector)based on hours flown, many people
howled that no one could possibly know how many GA hours are actually
flown. They used that to dismiss the idea that GA is heavily subsidized.
But the Nall study is accepted as science.