The market is already used to the September effect and many would want to close their position before September.
This is until now the explanation I would myself find the most convincing one, just for its "internal logic" - because afaik it's a pretty common phenomenon that traders always try to "anticipate" the market.
However, judging from the data in the graph above, I think the evidence for it is relatively thin. If this was a widespread phenomenon, then we should see two things:
1) a "deepening" of the September "crash"
2) an increasingly negative August price evolution, due to traders anticipating the "Downtember"
At least the first one is not occurring. It seems to me even that the September downtrend is less pronounced each year. It's possible however that this "phenomenon" is now so well known that it is exploited by other traders, the other way around (e.g. trying to liquidate shorts).
For factor 2 (August becoming worse) there could be some evidence, in the last two years there was a double-digit August decline. So I don't rule out there is really some "anticipation" effect here in place.
Schools usually start during this periods and let's not forget the financial crisis occurred in September
Maybe this has played a role but still the September effect has been going on way before the 2000's.
Ah, thank you, I didn't know that the
September Effect was really a thing in the stock market. Interesting.
Monday positive, Tuesday -wednessday evening negative, Wednessday night -friday positive, Saturday -unstable, Sunday -negative till night, and Sunday night till Monday positive.
It's interesting, I have also made observation on that matter, but for me there seem to be two different patterns:
- first, the "Monday/Tuesday dip" pattern. It isn't as common in the last weeks but was very pronounced in early 2024 (just after the ETF approval, some blamed GBTC selling)
- second, the "Monday boom - Midweek dip" which is now more common in the last weeks, and is similar to what you observed.
In both cases, however, weekends were quite stable and uneventful. I remember that in the early days of Bitcoin weekends were often an excuse for larger dips ("weekend dip" was a term you could google in 2013 or so).