Dr.PainCLE said:

The useful move here is to separate what is established from what is widely repeated.

There is a second half to this that has not been said yet. Whatever the answer turns out to be, the method for getting there is the same: state the assumption, do the arithmetic in public, and invite the correction. That is slower than asserting, and it is the only version that survives being wrong.

Adding the numbers, since they settle part of this. Say what you would expect to see if you were wrong, before you look. It is a small discipline and it changes what you notice.

Correct me if the detail matters more than I have assumed.

A narrower follow-up, since the general answer is now clear:

How would you tell the difference between that and the alternative explanation?

quinn_sf said:

Say what you would expect to see if you were wrong, before you look.

I am going to disagree with the direction of travel here. The thread has converged on the tidiest answer rather than the best-supported one, and those are not the same thing.

quinn_sf said:

Say what you would expect to see if you were wrong, before you look.

Agreed, with the usual condition: that holds for the average and this board is a collection of individuals. A population claim and a personal prediction are different things and get quoted interchangeably.