Code black turbo · market history

Pandemic Playbook

How fast COVID spread, what 100 stocks did, and the plan to write before the next outbreak. History, not a forecast, not financial advice.

Stocks 100 · benchmarks 13 · sector funds 11 · critic 21 of 21 fixed

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Start here

TL;DR

1
Sell only early, only a set slice, and buy it back on a schedule, never "near the bottom". Selling in the 2020 panic and waiting for the all clear left you 16% to 34% fewer shares. A slice sold at the alarm (Feb 21 to 26) and bought back in 4 weekly buys starting 2 weeks later left you 20% to 30% more, but the rule was picked knowing how 2020 went. In two false alarms the same rule cost 4% to 8%
Proof: the sell test; data/sell_early.md
2
Irkutsk today is Level 0, noise: make no trades and finish the Before lists. A lab worker died Oct 1 or 2 of a pneumonia that media called suspected plague. Russia says it was not plague, ECDC sees no secondary cases, and CDC sees no broader threat to the US. Still, four old outbreak stocks jumped 13% to 20% on Oct 5, and three of them gave back 4% to 10% the next day
Proof: Right now; data/irkutsk_spike.md
3
Prepare now, while shelves are full and lenders still lend. In 2020 Home Depot was rationing N95s by Feb 28, before US cases took off. Chase and Wells Fargo stopped new home equity lines in April. That April webcams sold out and Tylenol ran short in some regions, after the market had already bottomed. Two checklists, money and supplies, fix that today
Proof: Before the next one
4
The market ignored COVID for a month. The S&P 500 made a record close of 3,386.15 on Feb 19, 2020, 30 days after the first US case and 27 days after Wuhan locked down. The trigger was spread with no travel link (Italy Feb 21 to 23, California Feb 26), not the first case
Proof: Yahoo ^GSPC; CDC timeline
5
The crash took 23 trading days and almost nothing was safe. S&P 500 down 33.9%. 84 of the 100 stocks fell. Long Treasuries were the best shelter over the whole crash (+14.2%), yet in the worst week (Mar 9 to 18) they dropped 15.7% and gold dropped 12.5% as everyone sold for cash. Only T-bills and short Treasuries never moved against you
Proof: data/neutral.md, data/events.md
6
The bottom came from the Fed and Congress, not the virus. Mar 23, the morning the Fed said it would buy "in the amounts needed". US cases were 43,505 and doubling about every 2 days. 98 of 100 stocks rose from there to year end (median +72%)
Proof: Fed, Mar 23, 2020; NYT case data
7
Outbreak winners are rentals, not keepers. The stay at home group's median was +192% in 2020, then -72% over 2021 to 2022. 9 hype stocks from COVID, Ebola and mpox all at least doubled after their first spike day, then all fell 56% to 97% from the top. Bought on that spike day and held, the median result was -3%
Proof: data/chase.md, data/events.md
8
A man made outbreak from another country adds a war and sanctions layer. That country's stocks can be written to "effectively zero" (Russia 2022). Supply chains break, and defense money flows. Defense was NOT a crash hedge (Lockheed -36%, General Dynamics -43% in the crash). Lockheed, Northrop and General Dynamics won later instead (+45% to +85% over 2021 to 2022)
Proof: data/extra.md

How it works

In one picture

A pandemic hits markets like a hurricane hits a coastal town.

S&P 500 daily close, Jan 2 to Aug 31, 2020 (Yahoo ^GSPC, data/gspc_2020.csv). Dashed: the Feb 19 record, until prices got back to it.

Radar

The storm sits on the radar for weeks while everyone keeps shopping. That was January 2020.

Landfall

Prices break when it reaches your own streets. That was Italy and California in late February.

Rebuild money

The Fed and Congress decide when prices turn, not the storm. In 2020 the money was promised while the storm was still growing, so the market bottomed on Mar 23 with cases doubling every 2 days.

Right now

The Irkutsk plague watch

Checked Oct 7, 2026, 11:51 PM Denver. This story moves fast, so recheck the sources before you act on it.

Level 0, noise. Make no trades. Use the calm to finish the Before lists. A worker at Russia's Irkutsk Anti-Plague Institute died on Oct 1 or 2 (reports differ) after a severe pneumonia. Media called it suspected pneumonic plague. Russia says it was pneumonia of unknown cause, with no lab accident and no germ from her lab work found. The US State Department: "Many details have not been confirmed." No second case is confirmed. CDC: "no indication of a broader threat to the United States".

Date (2026)	What happened	Confirmed or reported	Source
Before Sep 29	Russian media said she dropped a test tube of live bacteria at work	reported; Russia's health watchdog rejects it	TimesLIVE
Sep 29 to Oct 2	She went into hospital in Shelekhov with severe pneumonia on Sep 29 and died on Oct 1 or 2. The hospital closed its inpatient ward	ward closure confirmed by the district mayor	Meduza
Oct 2	At least 197 contacts put under medical isolation, more than 100 of them in hospital wards	reported; the governor confirmed every contact is under observation	Moscow Times
Oct 4 to 5	Russia's health watchdog: "pneumonia of unknown etiology"; testing found "no microorganisms associated with the patient's professional activities"	official	AP
Oct 5 to 6	US State Department: "aware of reports of a fatal case of suspected pneumonic plague" and "Many details have not been confirmed." The old outbreak stocks jumped on Oct 5 (table below)	official	GMA
Oct 6	ECDC: "no reports of secondary cases and no evidence of sustained human-to-human transmission"	official	ECDC
Oct 7	WHO: Russia told it there was "no case of plague registered in this area". A second sick worker is reported but not verified	official; second case unverified	NBC

What would move it up the ladder

Level	For this outbreak it would look like
1 Watch	WHO or a lab outside Russia confirms plague; a second confirmed case among her contacts; Irkutsk limits movement
2 Alarm	confirmed cases outside the contact list, in another city or country, or on a flight; a drug resistant strain confirmed by WHO, CDC or ECDC (media reports do not count)
3 Panic	US cases with no travel link; emergency declarations; doxycycline or ciprofloxacin running short

If it is plague, what changes

Only the lung form spreads between people. CDC: "Pneumonic plague is the only form of plague that can be spread from person to person" (CDC), "via respiratory droplets, not fine aerosols" (CDC). Close contact matters more than shared air.
Speed decides it. WHO: "Pneumonic plague can be fatal within 18 to 24 hours of disease onset if left untreated" (WHO). CDC: "Plague can be cured with antibiotics, but treatment must be given quickly" (CDC). WHO: recovery rates are high if "treated in time (within 24 hours of onset of symptoms)" (WHO).
Close contacts (under 6 feet, sustained) get preventive antibiotics for 7 days (CDC).
So the home move is speed, not a stockpile. A sudden fever with a cough after a possible exposure means a doctor the same day. Do not treat yourself with stored or fish antibiotics. FDA: "Only take drugs that have been prescribed to you by your doctor and that you have gotten through a legitimate source" (FDA).
A strain built to resist drugs is the real tail risk. For an attack, CDC's guidance calls for "two different classes of antimicrobials" because resistance may have been engineered (CDC).

The old pattern, live. Our own Yahoo closes (data/irkutsk_spike.md). Oct 5 was the first trading day after the weekend reports. The outbreak stocks jumped, most gave a big part back the next day, and the S&P 500 barely moved. None of them sells a plague drug or vaccine (Lakeland and Alpha Pro Tech make protective gear).

Stock	Oct 5	Oct 6	Sep 28 to Oct 7
Novavax (NVAX)	+20.1%	-9.9%	+3.9%
Lakeland (LAKE)	+14.6%	-8.0%	+4.1%
Emergent (EBS)	+14.4%	-4.0%	+3.1%
Alpha Pro Tech (APT)	+13.0%	+4.2%	+18.5%
Arcturus (ARCT)	+12.5%	-11.3%	-11.7%
Moderna (MRNA)	+6.9%	-7.8%	-0.4%
SIGA	+3.0%	-5.5%	-5.8%
S&P 500 (SPY)	+0.7%	+0.5%	+1.5%

Plague outbreaks before. Madagascar 2017 was the big modern one: 2,348 cases and 202 deaths from Aug 1 to Nov 22, 1,791 of them pneumonic. It was contained in about 4 months, no case spread by travel, and WHO advised "against any restriction on travel or trade" (WHO). In Surat, India, "several hundred pneumonic plague cases" were reported by Sep 26, 1994 (CDC MMWR), and a large part of the city fled within days (secondary source).

During

The alarm ladder: what to watch, what to do

Level	What you see (2020 example)	What markets did	Money moves	Home moves
0 Noise	New illness reported abroad (Dec 31)	nothing	Note it. Nothing else	Finish the Before lists, a little each week
1 Watch	Person to person spread confirmed; a government locks down a city; cases in several countries (Jan 20 to 23)	ignores it; the obvious stocks pop	Reread this plan. Send new savings to T-bills instead of stocks; the only selling at this level is to pay off any margin. Price out protection while it is cheap (VIX was 14). Finish every Before row that needs a lender or an insurer: in 2020 those doors started closing in April	Fill any gap on the Supplies list now, while shelves are full. About five weeks after this level in 2020, Home Depot was rationing N95s
2 Alarm	Sustained spread in a second rich country (Italy); local cases with no travel link (Feb 21 to 26); cases doubling in under 4 days; companies warning about supply	first big down days	If your card names a slice, sell it now (the rule below). Buy protection now if you planned to. Finish the buy list with balance sheet checks. No new hype stock buys	One last calm trip: top up fresh food and household goods, then stop. Set up work and school from home
3 Panic	National emergency, lockdowns, trading halts, VIX over 50, gold and long bonds falling too (Mar 9 to 19)	crash, forced selling	Do not sell. Start buying in small, equal steps (weekly): four weekly buys from Mar 9 to Mar 30 made about +52% by Dec 31. Harvest tax losses by swapping into a similar fund	Stay home and shop rarely. Do not hoard: it empties the shelves for everyone else. Buy masks and medicine only from sellers you know
4 Turn	The Fed goes "unlimited" or similar, and a big relief bill moves (Mar 23 to 27)	bottom zone	Keep the buy back schedule, and put most of the savings you parked in T-bills to work, never the 6 to 12 months of bills money. Favor beaten down leaders that can survive a year with no revenue (Ramelli and Wagner: cash and low debt decided who held up)	Use your supply to skip the worst weeks. Some shortages lag the market: in April 2020, after the Mar 23 bottom, Tylenol ran short in some regions, webcams sold out, and meat plants shut
5 Exit	Strong vaccine or treatment results (Nov 9)	rotation	Sell the outbreak winners. Hold or add reopening names. Expect bonds and rates to move	Restock what you used, slowly, and keep these lists for next time

Daily sources for levels 0 to 2: WHO Disease Outbreak News · CDC Health Alert Network · CIDRAP · ProMED · Fed press releases · VIX.

Scenario matrix: what to lean toward and what to avoid, by kind of outbreak

COVID repeat (fast spread, low to moderate death rate, natural)

What it looks like: spread before symptoms, lockdowns
Likely market pattern: 2020: ignore, crash in weeks, policy bottom, huge rebound
Lean toward: cash for the dip; stay at home and test names EARLY only; hard hit quality names at the policy turn
Avoid: selling at the low; holding outbreak winners after vaccine news

Ebola or MERS type (slow spread, high death rate)

What it looks like: scary headlines, contained
Likely market pattern: a dip of 5 to 8%, recovers within months
Lean toward: do nothing big; maybe sell into the hype
Avoid: buying PPE or vaccine stocks after the first spike

Plague type (bacterial; common antibiotics cure it when started early)

What it looks like: a sudden scare, contacts quarantined, talk of a lab or a weapon
Likely market pattern: outbreak stocks spike for a day or two while the S&P 500 barely moves (Oct 5, 2026); if a drug resistant strain spreads between people, treat it as Worse than COVID
Lean toward: nothing new; finish the Before lists
Avoid: buying outbreak stocks on the spike day

Worse than COVID (fast and deadly)

What it looks like: longer lockdowns, real shortages
Likely market pattern: deeper and longer than 2020; some companies fail
Lean toward: staples, cash, short Treasuries, companies with net cash; buy in more, smaller steps
Avoid: borrowed money; companies deep in debt; anything needing a quick reopening

Deliberate attack blamed on a state

What it looks like: sudden, plus sanctions and maybe military moves
Likely market pattern: gap down on day one, plus a lasting hit to that country's assets and its suppliers
Lean toward: defense AFTER the first leg down; domestic suppliers; the dollar
Avoid: that country's stocks and funds; companies with big sales or factories there

Lab accident, origin disputed

What it looks like: slow attribution, political fights
Likely market pattern: like COVID, plus tariff and decoupling risk over time
Lean toward: as COVID
Avoid: same as above, slowly

Any outbreak while inflation is high

What it looks like: the Fed cannot just cut to zero
Likely market pattern: slower, weaker rebound; bonds may fall with stocks
Lean toward: short term Treasuries, cash, energy and commodity producers
Avoid: long bonds as a "hedge"; expensive growth stocks

Fast cure (vaccine or pill in months)

What it looks like: a cure news day like Nov 9, 2020
Likely market pattern: violent rotation: cruise, travel, energy and banks up, stay at home down
Lean toward: travel and reopening names at the cure news
Avoid: outbreak winners after the cure news

Your question

Should you sell some, then buy back near the bottom?

Yes to selling a set slice early. No to waiting for the bottom to buy back. Buying back is like filling up during a gas price war: fill up on four Mondays instead of hunting for the cheapest day, because you only learn which day was cheapest after prices climb back. The S&P 500 bottomed on Mar 23, 2020 while US cases were doubling every 2 days. Anyone waiting for it to look safe bought back after Aug 18, above where they sold.

The rule (write your slice on your card now, while you are calm):

Sell only at Level 2 of the ladder, and only the slice you wrote down in advance. Never at Level 3.
Do it with ETF shares (SPY, VOO and the like) inside an IRA. A sale there owes no tax. In a taxable account the tax on your gains comes off before you buy back, and many mutual funds block buying back for 30 days (Vanguard funds: "30 calendar days", ETF shares exempt, SEC filing).
Starting 2 weeks after the sale, buy the slice back in 4 equal weekly buys, whatever the news says.

What that did (shares you own after the round trip vs just holding; the 2020 rows use SPY with dividends, the false alarm rows the S&P 500 index; data/sell_early.md):

You sold	You bought back	Shares vs just holding
At the alarm: any close Feb 21 to Feb 26, 2020 (Level 2)	the rule: 4 weekly buys starting 2 weeks later	+20% to +30%
At the alarm	4 weekly buys from Level 3, Mar 9 to Mar 30	+25% to +34%
At the alarm	all at the exact bottom, Mar 23 (nobody knew it then)	+39% to +49%
At the alarm	after the all clear: Aug 18, back at the old high	-9% to -3%
In the panic: any close Mar 9 to Mar 23 (Level 3)	after the all clear, Aug 18	-34% to -16%
False alarm: SARS, Mar 12, 2003	the rule: 4 weekly buys starting 2 weeks later	-8%
False alarm: H1N1, Apr 24, 2009	the rule: 4 weekly buys starting 2 weeks later	-4%

How to read it: +30% means the round trip left you 30% more shares of that slice than holding would have; -16% means 16% fewer. On a 20% slice, the rule added about 4% to 6% to your stock holdings in 2020, and each false alarm cost about 1% to 2%. This is one real crash and two false alarms, so trust the direction more than the exact size. The 2 week wait and 4 weekly buys were picked knowing how 2020 went, so the 2020 rows flatter the rule. The false alarms are the fairer test, and their sales fall on the day the news broke, a little earlier than a strict Level 2. A second series gave the same ranges within 2 points (S&P 500 index closes for 2020, SPY for the false alarms).

Behind the answer

The evidence

The clock: COVID in 2020

Date	Event	Market at the time	Source
Dec 31, 2019	WHO told of "pneumonia of unknown etiology" in Wuhan	nothing	WHO DON229
Jan 20 to 21, 2020	First US case confirmed (Washington state, samples from Jan 18)	Novavax +71% and Alpha Pro Tech +39% on Jan 21; the index did not care	CDC; our data
Jan 23	Wuhan locked down (11 million people)	S&P keeps climbing	widely reported, not reread
Jan 31	US public health emergency		CDC timeline
Feb 19		S&P record close 3,386.15, VIX 14.38	Yahoo
Feb 21 to 23	Clusters in Lombardy, Italy		widely reported, not reread
Feb 24		first big down day; the crash starts	Yahoo
Feb 26 to 28	First US cases with no travel link (Solano County, CA); CDC: "likely due to community spread"	falling	CDC, MMWR
Mar 2	US passes 100 cases		NYT data
Mar 3	Fed emergency half point cut	no relief	not reread
Mar 9, 12, 16, 18	Market wide trading halts (circuit breakers)	gold and Treasuries start falling Mar 9	secondary; our data
Mar 10	1,000 cases		NYT data
Mar 11 to 13	WHO says pandemic; Europe travel ban; US national emergency		CDC timeline
Mar 15	Fed to zero plus $700 billion of bond buying		Fed, Mar 15
Mar 16		VIX record close 82.69	Yahoo
Mar 17	West Virginia becomes the 50th state with a case		NYT data
Mar 19	10,000 cases; doubling every 2 to 3 days	gold hits its low (-12.5% from Mar 9)	NYT data; Yahoo
Mar 23	Fed: buy "in the amounts needed" plus credit backstops	S&P low 2,237.40 (-33.9%)	Fed, Mar 23
Mar 27	CARES Act signed; 100,000 cases	rising	NYT data; CARES not reread
Apr 28	1,000,000 cases	still rising	NYT data
Aug 18		S&P back above the Feb 19 high	Yahoo
Nov 9	Pfizer and BioNTech vaccine works	Carnival +39%, Cinemark +45%, Zoom -17% in one day	our data
Dec 11 to 14	First vaccine authorized, first shot		CDC timeline

How fast it spread (confirmed cases, data/neutral.md):

Milestone	Date	Days after WHO notice	Days after first US case
First US case confirmed	Jan 20	20	0
S&P 500 record close	Feb 19	50	30
First US case with no travel link	Feb 26	57	37
100 US cases	Mar 2	62	42
1,000	Mar 10	70	50
All 50 states have a case	Mar 17	77	57
10,000	Mar 19	79	59
S&P 500 low	Mar 23	83	63
100,000	Mar 27	87	67
1,000,000	Apr 28	119	99

So: 6 weeks from the first US case to 100 cases, then 100 to 100,000 in 25 days. The market fell for 33 days (23 trading days) and bottomed 4 days before the 100,000th case and 5 weeks before the millionth. Tests were scarce in February and early March, so the real spread ran ahead of these counts (well known, not measured here).

What 100 stocks did

Picked by sector before computing any returns, winners and losers both. Hindsight still shaped the list: names like Zoom, Peloton and Novavax are famous because they won, so these group numbers run hotter than a random pick would. The sector fund table further down is the unbiased check.

How to read it: each number is the % change of the group's median stock (half the group did better, half did worse), dividends included, from the close on the first date to the close on the last date. Stay at home reads +192 under All of 2020: $10,000 in its median stock on Dec 31, 2019 was about $29,200 a year later. It reads -72 under 2021 and 2022: $10,000 held through those two years became about $2,800. Zoom shows the whole ride for one stock: $10,000 became about $49,600 in 2020, then fell back to about $9,970 by Dec 30, 2022. The last column is the fall from each stock's highest close of 2020 and 2021 to its lowest close after that, through 2022. Each column is its own window, so you cannot add them: a 50% fall needs a 100% rise just to get back to even. Every ticker is in data/returns.csv.

Group (how many): tickers	Before the crashJan 17 to Feb 19, 2020	CrashFeb 19 to Mar 23	ReboundMar 23 to Dec 31	All of 2020Dec 31, 2019 to Dec 31, 2020	After2021 and 2022	Vaccine newsNov 6 to Nov 9, 2020	Top to later low2020 to 2022
Stay at home (10): ZM PTON DOCU NFLX AMZN SHOP ETSY CHWY W TDOC	+15	-10	+173	+192	-72	-14	-86
Vaccines and pharma (10): MRNA BNTX NVAX PFE JNJ GILD REGN AZN VIR INO	+2	+24	+37	+71	+46	0	-52
Tests, lab and PPE (10): ABT TMO DHR QDEL DGX LAKE APT HSIC MMM CLX	+6	-25	+63	+39	-11	-7	-39
Staples and home (10): WMT COST KR PG CPB GIS KMB CHD HD LOW	+2	-16	+32	+19	+24	-5	-24
Big tech (8): AAPL MSFT GOOGL META NVDA AMD CRM TSLA	+9	-31	+102	+62	-15	-2	-62
Shipping (2): UPS FDX	-5	-22	+111	+61	-11	-4	-39
Airlines (6): DAL UAL AAL LUV JBLU ALK	-1	-63	+73	-27	-19	+18	-70
Cruise, hotels, casinos (11): CCL RCL NCLH MAR HLT H BKNG EXPE LVS MGM WYNN	-7	-57	+93	-12	-19	+20	-56
Energy (8): XOM CVX OXY COP SLB HAL APA DVN	-9	-68	+76	-36	+208	+15	-15
Banks and real estate (8): JPM BAC WFC C SPG MAC VNO BXP	-3	-50	+65	-33	+13	+18	-46
Restaurants, retail, venues (9): DRI CMG DPZ DIS LYV CNK M KSS TJX	+1	-51	+111	+10	-5	+15	-46
Defense and aerospace (6): LMT NOC LHX GD BA GE	+3	-39	+37	-8	+30	+5	-27
Biodefense (2): EBS SIGA	+6	-16	+70	+59	-40	-1	-64
Benchmarks: S&P 500 (SPY)	+1.9	-33.7	+69.8	+18.3	+5.3	+1.3	-24.5
Nasdaq 100 (QQQ)	+6.1	-27.9	+84.7	+48.4	-14.1	-2.0	-35.1
Gold (GLD)	+3.6	-3.6	+21.9	+24.8	-4.9	-4.4	-22.0
Long Treasuries (TLT)	+5.6	+14.2	-3.9	+18.2	-34.4	-2.1	-44.1
China internet (KWEB)	-2.5	-20.3	+83.8	+58.2	-57.8	-2.5	-80.9

Biggest winners, full 2020: Novavax +2,702%, Tesla +743%, Peloton +434%, Moderna +434%, Zoom +396%, Etsy +302%, Alpha Pro Tech +225%, Chewy +210%, DocuSign +200%, Shopify +185%.

Biggest losers, full 2020: Carnival -57%, Macerich (malls) -57%, Occidental -57%, Norwegian Cruise -56%, United -51%, Cinemark -48%, American Airlines -45%, Schlumberger -44%, APA -44%, Royal Caribbean -44%.

Up in the crash (16 of 100): Vir +114%, Alpha Pro Tech +110%, Inovio +74%, BioNTech +59%, Zoom +54%, Teladoc +43%, Moderna +40%, Lakeland +38%, Novavax +35%, Regeneron +14%, then Chewy, Domino's, Gilead, Quidel, Kroger and Clorox in single digits.

Best from the bottom: the 25 worst crashers rose a median 112% from Mar 23 to Dec 31, three times the 36% of the 25 that held up best. 9 of the 15 biggest rebounders had fallen more than the S&P, like Halliburton (-76%, then +264%) and MGM (-71%, then +244%). But the bounce did not undo the fall: half of those 25 crashers still ended 2020 down 35% or more, while the 25 best holders ended up 76% (median). By group, stay at home still led the rebound (+173% median).

What the table says

The obvious winners moved before the crash. The crowd only moved once the crash began.
The crash hit good and bad companies alike. The hardest hit bounced the most from the low, yet half of them still ended 2020 down 35% or more.
Outbreak winners were sold the day the vaccine news came, then gave back most of their gains over 2021 and 2022.
Energy went from worst to best once the economy reopened and the 2022 war hit. A crash group can become the next cycle's leader.
Bonds and China stocks were no shelter in 2021 to 2022: TLT -34%, KWEB -58%.

Unbiased check: the S&P 500 sector funds (nobody hand picked these; each fund's % change over the same dates, data/neutral.md):

Sector fund	Before the crashJan 17 to Feb 19, 2020	CrashFeb 19 to Mar 23	ReboundMar 23 to Dec 31	All of 2020Dec 31, 2019 to Dec 31, 2020	After2021 and 2022	Vaccine newsNov 6 to Nov 9, 2020
Technology (XLK)	+5.8	-31.2	+86.0	+43.6	-2.6	-0.7
Communication (XLC)	+1.6	-29.8	+68.3	+26.9	-27.7	-0.8
Consumer discretionary (XLY)	+3.3	-33.5	+84.8	+29.6	-18.5	-0.3
Consumer staples (XLP)	+1.0	-24.2	+41.8	+10.1	+16.3	-0.2
Health care (XLV)	-0.4	-27.9	+53.9	+13.3	+23.4	+0.9
Utilities (XLU)	+5.2	-35.4	+43.1	+0.5	+19.4	+1.9
Real estate (XLRE)	+4.2	-37.8	+47.5	-2.2	+7.8	+2.6
Financials (XLF)	+0.3	-42.8	+69.8	-1.7	+20.5	+8.2
Industrials (XLI)	-0.3	-41.6	+83.8	+10.9	+14.3	+3.4
Materials (XLB)	-1.0	-36.2	+91.6	+20.5	+11.8	+2.2
Energy (XLE)	-7.2	-56.1	+67.8	-32.7	+151.9	+14.3
S&P 500, equal weight (RSP)	+0.2	-39.0	+80.2	+12.7	+14.4	+4.3
S&P 500 (SPY)	+1.9	-33.7	+69.8	+18.3	+5.3	+1.3

Same direction, smaller size. The hand picked groups above exaggerate how big the moves were, not which way they went.
"Safe" sectors still fell hard in the crash: utilities -35%, real estate -38%. Staples (-24%) and health care (-28%) held up best.
The average stock fell more than the index (equal weight -39% vs SPY -34%). The biggest companies held the index up.

How often is it COVID? Other outbreaks

The index after outbreak news. How to read it: every number is the change from the index close on the day the news broke. Worst close is the deepest point in the next 60 trading days (about 3 months).

Event	Index	Worst closenext 60 trading days	6 months later	12 months later	Note
9/11 attacks (not an outbreak)	Dow	-14.3% (Sep 21)	+10.5%	-10.4%	markets shut 4 days
Anthrax letters, Oct 2001	S&P	-1.2%	+5.3%	-25.2%	inside the dot com bear market
SARS, Mar 2003	S&P	+3.4%	+25.7%	+37.6%	Iraq war began Mar 20
H1N1, Apr 2009	S&P	-1.3%	+24.6%	+40.5%	just after the 2009 low
Ebola, Sep 2014	S&P	-5.6%	+4.8%	-2.6%
MERS, May 2015	KOSPI (Korea)	-7.7%	-8.3%	-9.0%	Korea's outbreak
Zika, Feb 2016	S&P	-5.7%	+11.9%	+17.5%
COVID, Jan 2020	S&P	-32.6%	-1.9%	+16.0%
Mpox, May 2022	S&P	-6.5%	+0.9%	+7.0%	inside the 2022 bear market

6 of the 8 outbreaks had the index higher 6 months later. Only COVID caused a crash, because it brought lockdowns to a service economy. Baker et al.: "No previous infectious disease outbreak, including the Spanish Flu, has impacted the stock market as forcefully".

The hype stocks spike and fade (held from before the news: Jan 17, 2020 for COVID, Sep 2, 2014 for Ebola, May 6, 2022 for mpox, Sep 10, 2001 for anthrax). How to read it: Novavax, held from Jan 17, 2020, rose 5,474% to its top in Feb 2021, then fell 97% from that top. From the start to the end of 2022 it was up 79%, so the holder kept 1% of the gain it showed at the top.

Episode	Stock	Gain to peak	Peak date	Then fell from peak	Start to end of window	Share of peak gain kept
Ebola 2014	Lakeland (LAKE)	+334%	Oct 13, 2014	-73%	+108% by Sep 2015	32%
Ebola 2014	Alpha Pro Tech (APT)	+260%	Oct 13, 2014	-80%	-29%	none
Mpox 2022	SIGA	+272%	Aug 15, 2022	-80%	-14% by May 2023	none
Mpox 2022	Bavarian Nordic	+202%	Aug 3, 2022	-56%	+40%	20%
Mpox 2022	Emergent (EBS)	+17%	May 23, 2022	-79%	-73%	none
COVID	Novavax	+5,474%	Feb 2021	-97%	+79% by end 2022	1%
COVID	Vaxart	+6,039%	Feb 2021	-97%	+153%	3%
COVID	Inovio	+863%	Jun 2020	-96%	-53%	none
COVID	Alpha Pro Tech	+621%	Feb 27, 2020	-85%	+15%	2%
COVID	Lakeland	+305%	Feb 2021	-75%	+21%	7%
COVID	Zoom	+652%	Oct 2020	-88%	-10%	none
COVID	Peloton	+428%	Jan 2021	-96%	-75%	none
COVID	Moderna	+2,250%	Aug 2021	-76%	+771%	34%
Anthrax 2001	Bayer (Cipro maker)	+18%	Mar 2002	-56%	-48%	none

Bought on the first big spike day instead (first close up 20% or more, then held to Dec 30, 2022 for COVID, Sep 30, 2015 for Ebola, May 31, 2023 for mpox; data/chase.md). How to read it: Novavax first closed up 20% or more on Jan 21, 2020 (up 71% that day). Bought at that close, it later rose as much as 3,158%, ended 2022 up 5%, and fell 97% from its top to its later low.

Episode	Stock	Spike day	Best gain after	Held to the end	Peak to later low
COVID	Novavax	Jan 21, 2020 (+71%)	+3,158%	+5%	-97%
COVID	Vaxart	Jan 21, 2020 (+39%)	+4,302%	+81%	-97%
COVID	Inovio	Jan 27, 2020 (+25%)	+496%	-71%	-96%
COVID	Alpha Pro Tech	Jan 21, 2020 (+39%)	+421%	-17%	-85%
COVID	Lakeland	Jan 21, 2020 (+26%)	+223%	-3%	-75%
Ebola	Lakeland	Oct 1, 2014 (+30%)	+222%	+54%	-73%
Ebola	Alpha Pro Tech	Oct 9, 2014 (+28%)	+108%	-59%	-80%
Mpox	SIGA	May 20, 2022 (+43%)	+111%	-51%	-80%
Mpox	Bavarian Nordic	May 19, 2022 (+29%)	+120%	+2%	-56%

Every one at least doubled after its spike day, and every one then fell 56% to 97% from its top. Held to the end, the median was -3%. The money went only to whoever sold into the spike, and nobody knows the top in advance. (Emergent never had a +20% day in the mpox window.)

The rule: the product sells out but the stock round trips. The few that kept real gains sold a working product at scale: Moderna and BioNTech (vaccines; both rose again over 2021 to 2022, +72% and +87%), Bavarian Nordic (the mpox vaccine, +40%) and Lakeland in 2014 (protective suits, +108% a year later). Even Moderna fell 76% from its peak. Bayer sold more Cipro during the anthrax scare and its stock still fell; its Baycol drug withdrawal in Aug 2001 likely mattered more (from memory, not verified).

If it is man made and from another country

Area	Natural outbreak (COVID)	Man made, blamed on a foreign state
First days	Slow burn, weeks of denial	Can be a 9/11 style gap down: the Dow fell 7.1% the day it reopened in 2001 (to 8,920.70, our data) and 14.3% to the low, with the Fed cutting the same morning (Fed, Sep 17, 2001)
That country's assets	Fell, then recovered	Can go to zero and become unsellable. In 2022 index providers removed Russia at a price "effectively zero" (secondary source). China internet stocks fell 81% from peak on government action alone (KWEB, our data)
Supply chains	Shut, then reopened	Sanctions and decoupling last for years: medicine ingredients, electronics, rare earths. Tariffs passed "almost fully" into US import prices in 2018 (NBER 26610)
Defense	Fell with everything (Lockheed -36%, General Dynamics -43% in the crash)	Budgets rise, but the gains come after the crash: NOC +85%, GD +75%, LMT +45% over 2021 to 2022
Biodefense	Contracts, stock spikes, then fades	Bigger budgets (Project BioShield authorized "$5.6 billion" over 10 years, BARDA), but the spike and fade pattern still applies (Emergent -87% over 2021 to 2022)
Insurance	Virus exclusions; most business interruption claims lost (not verified)	Terrorism backstop (TRIA) needs a federal "certified act of terrorism" by a foreign person or interest. A lab accident likely would not qualify (regulator bulletins, not verified)
The rescue	Fed to zero, unlimited buying, about $2 trillion of fiscal relief (CARES, not reread)	Depends on inflation at the time. If prices are already rising, the Fed has less room, and bonds may not hedge (2022: stocks and bonds fell together)
Cyber	small	retaliation risk higher (judgment)

Honesty log: what is verified and what is not

Status	Claim
VERIFIED (computed here from Yahoo adjusted closes; scripts and CSVs in `data/`)	every stock, benchmark and sector fund return, the 2020 index levels, the VIX record, shelter moves inside the crash, the rebound by crash quartile, the past outbreak index moves, the hype stock peaks, fades and spike day buys, the Aug 18 recovery, staged buying results
VERIFIED (second source, `data/second_source.md`)	StatMuse closes match Yahoo: Zoom in the crash +53.5% and over all of 2020 +395.5% (Yahoo +53.5% and +395.8%); SPY $307.63 on Feb 19 and $203.91 on Mar 23 (Yahoo 307.64 and 203.91). The critic's own run matched Chewy, Delta, Exxon and Carnival within 0.3 points and read the S&P levels on FRED; my FRED requests timed out twice
VERIFIED (NYT covid-19-data)	US case milestones, doubling times, the 50th state date
VERIFIED (read on the primary page)	WHO Dec 31 notice; CDC timeline lines (Jan 20, Feb 28, Feb 29, Mar 11, Mar 13, Dec 11, Dec 14); MMWR community spread; Fed Mar 15, Mar 23 and Sep 17, 2001 statements; the Baker et al. quote; the BioShield $5.6 billion; the circuit breaker levels (investor.gov) and the wash sale rule (IRS Pub 550) in Words used
UNVERIFIED (secondary or snippet)	Wuhan lockdown, Italy, Mar 3 cut and CARES dates (well known, not reread); circuit breaker dates; Russia "effectively zero"; TRIA rules; insurance lawsuit outcomes; Ramelli and Wagner; the NBER 26610 "almost fully" tariff quote; the Bayer Baycol cause; the 2020 bankruptcies
Survivorship	Companies that went bankrupt or were delisted are missing. HOLX and OMI returned no data and were swapped for DGX and HSIC before any results were read. So the losers look a bit better than they were
Selection bias	The 100 names were picked by sector before computing returns, but by someone who already knew 2020. Famous winners like Zoom, Peloton and Novavax inflate the stay at home and PPE groups both ways (the gains and the later falls). The sector fund table is the unbiased check: same direction, smaller size
Spin-off risk	PFE's Viatris spin-off (Nov 2020) shows no jump in the data, so it is probably adjusted; RTX was replaced with LHX to avoid the Apr 2020 spin-offs
Hindsight	The windows use dates we know now. In real time nobody knew Mar 23 was the low. That is why the plan buys in steps. The sell rule's 2 week wait and 4 weekly buys were chosen knowing how 2020 went, so its 2020 result flatters it; the two false alarms are the fairer test
VERIFIED (read on the source page, Oct 7 to 8, 2026)	the Irkutsk timeline lines (TimesLIVE, Meduza, Moscow Times, AP, the State Department via GMA, ECDC, and WHO and CDC via NBC); WHO's Madagascar 2017 numbers; the CDC MMWR line on Surat; Vanguard's 30 day rule and its ETF exemption (SEC filing)
REPORTED, NOT CONFIRMED	the test tube story; the contact counts; the second sick worker; whether she died on Oct 1 or Oct 2
VERIFIED (computed here)	the Oct 5 spike table (`data/irkutsk_spike.md`); the sell test (`data/sell_early.md`), rerun on a second price series (S&P 500 index for 2020, SPY for 2003 and 2009) and within 2 points
UNVERIFIED (secondary)	how much of Surat fled in 1994
VERIFIED (read on the source page, Oct 8, 2026)	every quote and number in the Money and Supplies checklists (SEC, FDIC, HousingWire, PYMNTS, LendingTree, 12 CFR 1026.40, FINRA, InvestmentNews, CFPB, IRS, the SOA survey, AP, Colorado SOS, Ready.gov, Business Today, HHS, CDC, PBS, NIOSH, NielsenIQ, CBS Miami, WEAR, TechXplore) and in the plague list (CDC, WHO, FDA)
SECONDARY or LOCAL	the toilet paper numbers (Nielsen and IRI as reported by local TV stations) and the Clorox quote (a local TV station); the thermometer and freezer sellouts are single stores in Jacksonville, one example each, not national counts
ESTIMATE (mine)	the amounts marked "my estimate" in Supplies; 6 to 12 months of emergency cash; the 20% slice in the sell example
VERIFIED (independent re-derivation, Oct 8, 2026)	a separate worker rebuilt the sell table from the written rule and raw prices without seeing my numbers. All 7 rows matched within rounding, on SPY with dividends and on the S&P 500 index. If the weekly buys are counted in trading days instead, the H1N1 row moves from -4% to -5%
Judgment	the scenario matrix and alarm ladder (including its Home moves) are my synthesis, not sourced forecasts; so are the Level 0 call on Irkutsk and the plague row
Critic (independent, opus)	NOT READY with 6 findings; all 6 fixed. Finding 2 was half right: by group, stay at home led the rebound; by stock, the 25 worst crashers led. The report now says both. It found no error in the numbers, and the hurricane picture held
Critic 3 (independent, opus, Oct 8, 2026)	no blocking issues; 7 should fix and 5 nits, all fixed. It caught a quote credited to CDC that is WHO's (the 24 hour treatment window), card advice that contradicted its own source, N95 rationing placed before the crash, and ladder cash moves a reader could take as selling at Level 1 or spending the bills money at Level 4

Words used

Word	Meaning
VIX	the price of storm insurance for stocks: when traders expect big swings, they pay more for options and this number rises. It is the expected size of S&P 500 swings over the next 30 days, read from option prices. Around 14 is calm; over 50 is panic
SPY	the whole S&P 500 in one ticket, like buying the entire grocery aisle in one cart. A fund that holds all 500 companies; its returns here include dividends
T-bills, short Treasuries	like lending a trusted friend money until next payday: it comes back soon, so there is little time for anything to go wrong. US government IOUs that come due within a year (T-bills) or in 1 to 3 years. Their prices barely move
Long Treasuries	the same trusted friend, but a 20 year loan: you will be repaid, yet you are locked in so long that the IOU's resale price swings whenever interest rates move. US government bonds due in 20+ years (TLT). Usually rise in a scare, but swing hard
Margin	like a home equity loan where the bank can sell your house the moment its price drops too far. Money borrowed from your broker against your stocks. If prices fall far enough, the broker sells for you
2x or 3x funds	a gas pedal wired to double or triple every move: fine on a straight road, brutal on a twisty one. Funds that aim for 2 or 3 times the index's move each day. In choppy markets they drift below that, and a crash can wipe out most of their value
Protection	home insurance for your stocks: a fee you pay now that pays out only if prices fall below a level you pick. Usually put options (the right to sell at a set price until a set date). If prices do not fall, the fee is gone. It costs less when the VIX is low
Circuit breaker	like the breaker in your electrical panel, it trips when the load gets dangerous, but this one flips back on after 15 minutes and the fall can go on. A 15 minute halt of all US stocks when the S&P 500 falls 7% below the prior day's close before 3:25 PM Eastern (again at 13%; a 20% fall at any time ends the day)
Rebalance	like two glasses kept filled to set marks: when one rises past its mark and the other drops below its own, you pour from the high one into the low one. Selling some of what rose and buying what fell, to get back to your target mix. After a crash, that means buying stocks
Net cash	like a household with more in savings than it owes, which can ride out a lost job. A company whose cash is bigger than its total debt, so a bad year is far less likely to sink it
Adjusted close	like counting the interest along with the balance. The closing price with dividends and splits folded in, so a return is what a holder actually got
Median	like the middle kid when a class lines up by height: half are taller, half are shorter, and one giant at the end cannot pull the middle up. The middle value when a group is sorted from lowest to highest, so one wild stock cannot drag it
ETF	like a basket that shoppers trade with each other all day instead of returning it to the store, so the store's return rules do not apply. An exchange traded fund: its shares trade on the exchange like one stock, so a fund company's 30 day buy back block does not cover them
Equal weight	like grading a team by every player's average instead of letting the stars count most. An index where every company counts the same, so it shows the average stock instead of the giants
Tax loss harvesting	like swapping Coke for Pepsi, not canned Coke for bottled: you still hold a cola, and the sale books the loss. Selling a loser to book the loss for taxes and buying a similar fund that tracks a different index, so you stay invested. The wash sale rule blocks the loss if you or your spouse buy the same or a substantially identical holding within 30 days before or after, in any account, IRA and Roth IRA included. A blocked loss usually moves into the new shares' cost and counts when you sell them; an IRA buy loses it for good

Files (click a name to copy its full path)

PLAN.md README.md data/fetch_returns.py data/returns.csv data/prices_adjclose.csv data/summary.md data/event_checks.py data/events.md data/extra_checks.py data/extra.md data/neutral_checks.py data/neutral.md data/chase_checks.py data/chase.md data/second_source.py data/second_source.md data/chart_data.py data/gspc_2020.csv build_html.py data/sell_early.py data/sell_early.md data/irkutsk_spike.py data/irkutsk_spike.md

	Emergency cash for 6 to 12 months of bills, outside the market: a government money market fund, T-bills, or bank deposits under $250,000 per bank.So you are never forced to sell at the low. In mid March 2020 investors pulled $134 billion out of prime and tax exempt money market funds while government funds took in $838 billion (SEC). FDIC insurance covers $250,000 per depositor, per bank, per ownership category (FDIC).
	No margin, no 2x or 3x funds, no options you cannot afford to lose outright.Borrowed money turns a dip into a forced sale.
	A target mix (stocks, bonds, cash) and a rule to rebalance back to it when stocks fall 20%.That rule would have bought into the 2020 crash automatically, with no forecast needed.
	A buy list: 10 to 20 companies you would love to own 40% cheaper.Check net cash or low debt, and that they can survive a year of weak sales.
	A one page "if it happens" card: this ladder, the slice you would sell at Level 2, and your amounts per step.In week 3 of a crash nobody thinks clearly. Decide while you are calm.
	Backup credit opened now: a home equity line left at zero, and each spare card kept active with one small recurring bill paid in full every month. For bills, never for investing.Chase stopped taking new home equity lines on Apr 16, 2020, while open lines kept working (HousingWire); Wells Fargo stopped on Apr 30 (PYMNTS). In a July 2020 poll, 34% of cardholders had a limit cut in the prior 60 days (LendingTree). Its fix for a card you rarely use: "a small, recurring subscription" on it, "to ensure that it is used each month". A lender can still freeze an open line if home prices fall far (12 CFR 1026.40).
	A second brokerage account with some money in it, a tested login, and each broker's phone number on your card.Robinhood's site and apps went down on Mar 2 and 3, 2020, and FINRA later ordered over $5 million in restitution (FINRA via Mondo Visione). When the vaccine news hit in Nov 2020, Schwab, E*Trade, TD Ameritrade, Robinhood, Fidelity, Merrill and Vanguard all had login or speed problems (InvestmentNews).
	Know who owns your mortgage, and read your 401(k) loan and withdrawal rules.In 2020 relief depended on both. A federally backed mortgage got a 180 day payment pause on request, extendable by 180 more, and the missed payments were still owed (CFPB). Congress allowed retirement plan withdrawals up to $100,000 with no 10% penalty, but each employer chose whether to offer them (IRS).
	Life or disability insurance you need, bought and through underwriting now.In an Apr 2020 survey of 36 insurers, over half had restricted new policies for people back from travel to certain countries, and about half for high risk age groups (SOA, LIMRA and Oliver Wyman).
	A will, a health care directive and powers of attorney, signed in person, with scans saved.In March 2020 lawyers reported a rush on wills and held signings in parking lots and driveways (AP via Bangor Daily News). Colorado allowed remote notarizing only from late March, under an emergency order (Colorado SOS).

	Prescriptions: a 90 day supply of each where your plan allows, plus a written list of doses. 90 daysOn Mar 4, 2020 India, the world's main supplier of generic drugs, restricted exports of 26 drug ingredients and their medicines, including paracetamol, the main ingredient in Tylenol (Business Today). HHS: "Periodically check your regular prescription drugs to ensure a continuous supply in your home" (HHS, 2009).
	N95 masks with a NIOSH approval number printed on them (TC-84A-xxxx). about 10 per adult (my estimate)By Feb 28, 2020, before US cases took off, Home Depot limited N95s to 10 per person (PBS). On Apr 23 NIOSH warned of "an unprecedented number of falsified claims of NIOSH approval" (NIOSH).
	Food and water for two weeks: food you already eat that keeps, and 1 gallon of water per person per day. 14 days; water 14 gallons a personHHS: "Store a two week supply of water and food" (HHS, 2009). In the last week of Feb 2020, before any US lockdown, sales of dried beans rose 37% and canned meat 32% (NielsenIQ). Ready.gov: "one gallon per person per day for several days, for drinking and sanitation" (Ready.gov).
	Toilet paper, soap, hand sanitizer with at least 60% alcohol, and disinfecting wipes. about 4 weeks (my estimate)Toilet paper sales jumped about 213% in the week ending Mar 14, 2020 (Nielsen, via FOX6), and 21% of those shelves were empty again on Nov 18 (IRI, via KWTX). In Dec 2020 Clorox said its wipes shortage "could last until mid-2021" (WBKO). The 60% rule is CDC's (CDC).
	Fever and cold basics: a digital thermometer, fever reducers, cough medicine and electrolyte drinks. 1 thermometer; 1 pack of each per adult (my estimate)On Apr 6, 2020 Johnson & Johnson reported "a temporary shortage in some regions in the US" of Tylenol (CBS Miami). On Apr 3 Walgreens in Jacksonville was sold out of thermometers (News4JAX). HHS lists "pain relievers, stomach remedies, cough and cold medicines, fluids with electrolytes, and vitamins" (HHS, 2009).
	Freezer space for about 2 weeks of meat, or a small chest freezer if you have no room. optionalAbout 22 meat plants shut in the month to Apr 28, 2020 (WEAR). In May an appliance dealer said: "We sold all our freezers in April" (News4JAX).
	A laptop and a webcam for each person who would work or study from home. 1 eachOn Apr 8, 2020 Logitech was "sold out of every one it makes", and Amazon and Best Buy were out of stock (TechXplore).