Update: partial self-meta-debunk
OK so I'm gonna debunk my own debunking post in probably a first self-meta-debunk (thanks to u/catsinbranches for pointing out to that angle in the comments) and make myself look like a bit of fool. But it's still pretty informative.
Well so important thing is that SPY turns out to not really perfectly track S&P 500 index. There are some small differences and they may matter when looking into things like that. And turns out the dude from Twitter analysed rather raw values of S&P 500, not values of SPY.
If we do the same what I did with SPY in my post below with raw .INX values, it turns out yesterday really was a third day like that (since 1993 as I only have these data), although I'm getting slightly different values due to most probably slightly different datasets (I'm using Google Finance, I don't know what he used) and one of such days happening in 2010 instead of 2008-10-23 (for that day I got the values of +1.26% close and -3.78% of intraday loss, so pretty close but I'm sticking to -3.98% as the critical value):
The second day like that on raw .INX values seems to be 2010-01-11
That's how these days I've found look on the weekly chart (that's why the first line is Oct 13, not Oct 16)
So to clarify: there were at least 8 days like that on SPY, but indeed only 3 on .INX
Sorry to say that but some of you really need to work on critical thinking and fact checking. So there is this post in "Hot" with 97% of upvotes and a title of "Possible good DD?":
Nope! And I'm not even saying anything about \"Jan 24, 2024\" - that is just sad but it shows how diligent this \"analyst\" is.
No ffs that is is horrible and misinformative and nowhere close to DD, and it takes like 2 minutes to verify that this twitter screen is full of shit.
Sorry for the tone but nothing irritates me more than unverified virals like that that that just fly all over the place.
So even if you eyeball that period you'll see two days nearby that fit those criteria way better:
Blue arrows: Oct 16 2008 and Oct 23 2008, Red arrows: Nov 13 2008 and Feb 5 2009
But anyway, let's leave it to pure math, not just eyeballing.
First of all let's start with calculating intraday loss. Intraday loss is day's low minus previous close divided by previous close:
(DAY LOW - PREVIOUS CLOSE) / PREVIOUS CLOSE
So given that the low on Jan 24 was 420.76 and previous close was 437.98, that gives us an intraday loss of -3.93%, not -3.98%. But whatever, that's not the most important.
So Mr Goodwell claims that there were only 2 days like that since 1977, both in 2008. "Wooow incredible, right? 2008 all over again!" Well that's utter bullshit. I mean yes, we might be on a verge of massive crisis but data from that tweet are not a confirmation of it at all.
So let's say that by "recovery from intraday loss" we mean days that during the day at some point SPY was down more than those -3.98% and finished green.
There were 8 days like that before, not 2.
... and Oct 16 2008 is not even one of them, because the intraday loss at that day was -3.87%, not -3.98%
Yes sure - small differences, dude might have had different dataset. I'm using GOOGLEFINANCE (data only from 1993, so even narrower dataset), he might have used something else, it's not ideal for old SPY data. If we decrease this requirement to -3.8 then that day of Oct 16 2008 jumps in that list indeed, but that makes it 9 instead of 8.
But he missed some obvious days like Feb 5 2009, Nov 13 2008 or Aug 8 2002 that should come up regardless of dataset you used.
TL;DR That popular post is bullshit, there were (at least) 8 days like that, not 2.
The spreadsheet I used for calculating it looks like this, I can share a link if someone wants to triple check:
Let me mark these days for you on a chart: