**** SATURDAY/SUNDAY, MARCH 14 - 15, 2020 ~ VOL. CCLXXV NO. 61 WSJ.com HHHH$5.

THEWALLSTREETJOURNALWEEKEND

2009, Congress declared Pi

Day a national holiday. Some

venues have canceled Pi Day

events that draw crowds be-

cause of coronavirus.

But the real rain on Pi Day’s

parade: the taus.

For Michael Hartl, the holi-

day just doesn’t add up. In

some circles, math fans think

people should be celebrating

Tau Day instead.

Ask Dr. Hartl about it, and

he will unleash a litany of equa-

tions, all of which would be

simplified by using a different

never-ending constant—equal

to two times pi, and beginning

with 6.28. Dr. Hartl, a 46-year-

old physics Ph.D. and author of

programming tutorials, calls

Please turn to page A

From its humble beginnings

more than 2,000 years ago,

pi—that never-ending number

that starts with 3.14—has be-

come the superstar of mathe-

matical constants.

Schoolchildren celebrate Pi

Day on March 14. Math geeks

make it their wedding day. In

BYROBERTMCMILLAN

Nothing Can Spoil Pi Day—Except Maybe Tau

iii

Math rebels think they have a better idea; ‘geekier version’

Bernie Sanders concedes

he is losing the battle for the

Democratic presidential nomi-

nation. But the Vermont sena-

tor is still fighting a bigger

war: his lifelong crusade to

push the party’s economic

agenda to the left.

The candidate wants to

dramatically expand govern-

ment in order to address “the

grotesque level of income and

wealth inequality in this

country,” as he put it

Wednesday.

Mr. Sanders’s uncompro-

mising adherence to his lib-

eral ideals has been both his

strength and weakness in this

campaign. It energizes his

core supporters, who favor

his purity over more flexible

BYJACOBM.SCHLESINGER

America’s

Forgotten Epidemics

REVIEW

WSJ

The New

Face of 50?

OFF DUTY

ple said.

The central role of FAA offi-

cials Stacey Klein and William

Schubbe in the criminal probe

hasn’t been reported before. It

suggests Justice Department

prosecutors and federal inves-

tigators are seeking to center a

Please turn to page A

 FAA probes in-flight crack on

Southwest jet............................ A

rivals. But it has also turned

off Democrats who dislike his

ideas or worry they are unre-

alistic, and that his stubborn-

ness would keep him from the

give-and-take necessary to ac-

complish change in Washing-

ton. As Mr. Sanders himself

has acknowledged, many also

worry that his far-left posi-

tion could make it hard to

draw enough voters to beat

President Trump in a general

election. The escalating coro-

navirus crisis might also

make Americans more risk-

averse in choosing a leader.

Mr. Sanders argues that

voters agree with his plat-

form, even if they are skepti-

Please turn to page A

 Campaign rallies, fundraisers

go virtual...................................... A

Boeing Probe Centers on Claim

MAX Trainer Misled Regulators

Federal authorities are seek-

ing to build a criminal case

against a former Boeing Co. pi-

lot based on statements from

U.S. air-safety regulators who

say he failed to provide them

crucial details about the 737

MAX jet’s flight-control system,

according to people familiar

with the matter.

A pair of Federal Aviation

Administration officials who

dealt with Boeing pilot Mark

Forkner on pilot-training re-

quirements for the FAA’s ap-

proval process years before

dual crashes of the MAX are

now considered key witnesses

in the investigation, these peo-

ByDave Michaels,

Andy Pasztor

andAndrew Tangel

Sanders, Despite

Losses, Sticks to

Economic Vision

Candidate knows he’s losing the Democratic

nomination but aims to push party to left

It was the wildest week on

Wall Street since the 2008 fi-

nancial crisis.

It began on Sunday with a

sharp drop in oil prices that

pulled down stocks, already

battered following a selloff

sparked by the worsening cor-

onavirus outbreak. Investors

piled into U.S. government

bonds, pushing yields to re-

cord lows. By Wednesday, the

11-year bull market for U.S.

stocks was dead.

Bank executives promised

President Trump they would

keep lending but nervously

watched as companies tapped

their credit lines and hoarded

cash. Cracks formed in the

plumbing that moves money

through the financial system.

By Friday, central banks

around the world were trying

to salve the market by flood-

ing it with cheap money, to lit-

tle effect.

Stocks closed sharply

higher Friday, after President

Trump, bowing to widespread

pressure, declared a national

state of emergency and neared

a deal with congressional lead-

ers on a coronavirus aid pack-

age.

Yet global markets closed

one of their most bruising

weeks in history. Thursday

saw the biggest single-day

percentage decline in the S&P

500 since 1987; Friday the big-

gest single-day gain since

Please turn to page A

BYLIZHOFFMAN

Diary of

ACrazy

Week in

Markets

ends life across the country.

Mr. Trump, speaking in the

White House’s Rose Garden on

Friday, said the national-emer-

gency declaration would pro-

vide access to up to $50 bil-

lion in financial assistance for

states, localities and territo-

ries. He also called on every

U.S. state to immediately set

up emergency-operations cen-

ters and every hospital in the

nation to activate emergency

preparedness plans.

“No resource will be

spared,” the president said.

Stocks rose sharply, with

the Dow Jones Industrial Aver-

age rising nearly 2,000 points,

nearly gaining back its loss

from the previous day.

But as the pandemic contin-

ued to force school cancella-

tions and other disruptions,

the problem of a lack of tests

and a dwindling supply of the

products and chemicals

needed to make those tests

loomed as a threat. Top ad-

ministration officials have told

lawmakers they are aware the

supplies are short after a slow

and troubled start by the fed-

eral government.

House Democrats and the

White House reached a deal

Friday on legislation that

would make coronavirus test-

ing free and provide paid sick

leave to people affected. Mr.

Trump said in a tweet that he

Please turn to page A

Move frees up billions

to combat pandemic;

Democrats, White

House reach a deal

WASHINGTON—President

Trump declared a national

emergency over the coronavi-

rus pandemic, a move that he

said would free up billions in

assistance to states and give

him additional authority as

the rapidly spreading virus up-

ByAndrew Restuccia,

Jennifer Calfas,

Alejandro Lazo

andSam Schechner

Trump Declares Virus Emergency

JOHN MINCHILLO/ASSOCIATED PRESS

Medical personnel arrived Friday to open a drive-through virus-testing facility in New Rochelle, N.Y.

to the intensive care unit and

gathered the nurses.

“This is going to change

your lives,” the doctor told

them.

Twenty miles away in an-

other Seattle suburb, Yuan-Po

Tu, head of infectious diseases

at the Everett Clinic, was

awaiting the results of a coro-

navirus test for a sick 17-year-

old. Like the two Evergreen-

Health patients, the teenager

had no recent history of travel

abroad. The test came back

positive. Dr. Tu sent an urgent

email to his bosses.

“Houston, we have a prob-

lem,” he wrote.

In the two weeks since that

day, coronavirus has ripped

through the Seattle area, in-

fecting more than 436 people,

killing at least 35 and forcing

mass shutdowns of schools and

public events.

Medical professionals in

Please turn to page A

KIRKLAND, Wash.—Francis

Riedo was working late in his

office at EvergreenHealth hos-

pital the night of Feb. 28 when

a colleague at the Seattle &

King County public health de-

partment called with alarming

news: Two elderly patients

whom Dr. Riedo had picked to

test for the new coronavirus

were positive. Dr. Riedo hurried

BYDANFROSCH

ANDJIMCARLTON

Shortages, Delays Clouded

Response on the Front Lines

President Trump bumped elbows with Bruce Greenstein, an

executive at home-health firm LHC Group, at the White House.

EVAN VUCCI/ASSOCIATED PRESS

THE

CORONAVIRUS

PANDEMIC

Stock markets surge to

regain some ground, B

The week the world shut

down, in photos, A8-

Supply of products,

materials used for

testing falls,A

EXCHANGE

Businesses look for a way

forward and assess the

risk of the coronavirus, B

Stocks madea stunning
rally in the last minutes of
the trading session to push
indexes to their best single-
day gains since 2008. The
Dow rose 1,985 points, or
9.4%, to 23185.62. The S&P
500 and the Nasdaq each
jumped 9.3%.B
Investors are fleeingstock
funds at the fastest pace since
the bruising market selloff at
the end of 2018 while racing
into government bond funds
at a record clip.B
The four biggestcruise
lines said they were sus-
pending much of their oper-
ations until April.B
Hotels reelingfrom the
outbreak are cutting room
rates and starting to re-
duce staff.B
Xerox saidit is putting
its campaign to take over
HP on hold, a sign that the
pandemic is affecting deal
making.B

Federal authoritiesare
seeking to build a criminal
case against a former Boeing
pilot for allegedly misleading
the FAA about the 737 MAX’s
flight-control system.A

Microsoft co-founder
Gates is stepping down
from the company’s board
of directors.B

Several stakeholdersof
Harvard Business School
are pushing for a new
dean who will raise aware-
ness on issues such as cli-
mate change.B

What’s

News

CONTENTS
Books..................... C7-
Food......................... D6-
Heard on Street...B
Markets.................... B
Obituaries............... A
Opinion.............. A15-

Sports....................... A

Style & Fashion D2-

Travel...................... D4-

U.S. News............ A2-

Weather................... A

Wknd Investor....... B

World News.......... A

s2020 Dow Jones & Company, Inc.

All Rights Reserved

>

T

rump declaredana-
tional emergency over
the coronavirus pandemic,
a move that he said would
free up billions in assis-
tance to states and give him
additional authority to ad-
dress the outbreak.A1, A4-
House Democratsand
the White House reached
an agreement on legisla-
tion to make virus testing
free and provide paid sick
leave to people affected.A
Federal workers,law-
makers and some govern-
ment health experts
stepped up calls to close
government offices.A
South Korea and Italy
offer two bookends of how
to tackle the pandemic.A

Bayer has agreedon
draft settlement terms in
suits alleging its Roundup
weedkiller causes cancer.A

A federal appeals court
announced it will recon-
sider whether McGahn
must testify in a congres-
sional probe of Trump.A

Florida lawmakers
passed an E-Verify bill that
removed the most stringent
enforcement provisions.A

Israel’s Netanyahuand ri-
val Gantz will discuss form-
ing a unity government.A

Iraq reacted angrilyto
U.S. airstrikes against an
Iran-backed group.A

World-Wide

Business&Finance

NOONAN

‘Don’t Panic’ Is a

Rotten ResponseA