I'm pretty sure I've seen this pattern of "Stocks (tumble|gain) as X happened" but then 2 hours later if the stocks go in the other direction, there is a new headline "Stocks (tumble|gain) as X happened" where X remains the same, but tumble|gain got swapped.

I think I originally read that this happens in a book somewhere, then observed and noticed yeah that seems to be the norm. Not surprised it seems to be same thing in these adjacent metric % headlines where there's no proper thought if there exists a causal link between X and Y.

I think my brain has learned to recognize the pattern "Something rises X% as Thing Happened" and it reminds me of that cheeky quote about how every headline that is in the form of a question is, ... uh I forgot the full quote. But feels like almost this could have some kind of cheeky rule of its own, about how no causal link ever exists in a headline like this.

> a book somewhere

Black Swan by Nassim Taleb?

I think not, because doesn't ring a bell at all. It was a book related to stock market though, IIRC it was a Canadian author who described their career as a day-trader and how they thought of how markets work. I wish I remembered better but it was quite long ago, and I don't have said book anymore. My book likely came out after that book, so maybe my author picked it up from others.

That book however you mentioned, I just looked it up and it seems interesting. Might put on my read list.

Michael Lewis wrote a ton on this topic. He's not Canadian, but his books are really good, if financial non-fiction is your thing. He wrote The Big Short, among others (Flash Boys is a good one).

More sellers than buyers.