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July 9, 2020

Economic Impact of COVID-19
Does Social Distancing Explain Variation in COVID-19
Infection Rates? A Cross-Regional Analysis
By Marios Karabarbounis, Matthew Murphy, and Nicholas Trachter
Does compliance with social distancing mandates explain regional variation in COVID-19
infection rates? For example, Europe was hit hard
by the pandemic early on, but infection rates
have steadily decreased since April, even as European governments have relaxed lockdown measures and opened borders to travelers from other
European countries. In contrast, the United States
is experiencing a resurgence of daily cases driven
by outbreaks in the south and west. Arizona, California, Florida, and Texas currently account for 50
percent of new daily cases in the United States.
Both pundits and policymakers have pointed to
a lack of social distancing to explain the differing
trend in the United States. In this article, we study
this hypothesis using mobility measures such as
“time spent at home” or “time spent at retail” as
an indicator of social distancing.
Regional Differences in Infection Rates
and Deaths
Using data from Johns Hopkins Coronavirus
Resource Center and Google Statistics, Figures
1 and 2 present daily confirmed infections and
daily deaths per 1,000,000 inhabitants for Asia
(excluding China), Europe, South America, and
the United States. (Figures begin on p. 4. Countries included in the calculations are listed on p.
7.) Europe and the United States follow a similar

July 2020 – Richmond Fed

trajectory until early June. After that, daily confirmed infections in the United States rise sharply
but continue to decline in Europe. (The U.S.
death rate does not exhibit a similar increase in
our sample. This could be because there is a lag
of several weeks between infection and death
or because the demographics of those infected
has changed.) In any case, many are wondering about the United States’ lack of containing
the growth of daily infections. Were European
governments’ responses to the pandemic more
efficient than the U.S. government’s response?
Did European citizens comply more with social
distancing guidelines than U.S. citizens?
Regional differences are also apparent looking
at Asia and South America. South America has
been called the new epicenter of the epidemic,
as many countries are seeing the daily count of
both infections and deaths steadily increase.
The total number of cases is around four times
higher than the number in April. Many observers blame the deteriorating situation on the
inadequate government response. Many governments played down the severity of the threat.
For example, Brazil, the most populous country
in the region, has given out guidelines but has
not imposed national restrictions amid a major
COVID-19 outbreak. On the flip side, however, Ar-

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gentina and Colombia imposed strict social distancing measures, but daily infections still soared. Asia
(excluding China) is also experiencing an increase,
albeit much smaller than South America, driven by
India and Pakistan. India enacted a lockdown measure early in March, but this measure did not prevent
workers from fleeing cities and returning to their
villages in crowded buses and trains. In Pakistan, the
government eased the nationwide lockdown despite
warnings from health experts.

America reduced their time outside home to a
larger degree than Europe and the United States
during the first couple of months of the pandemic, which seems to contradict the strong increase
of daily infections observed in those regions. For
example, in the average South American country,
time spent at home is currently 20 percent higher
than on March 2, while in the United States it is
10 percent higher, and in Europe it is just 5 percent higher.

Time Allocation Across Regions
One way to study the connection between social
distancing and infection rates is to use mobility
measures as proxies for social distancing. To this end,
we use data from the Community Mobility Reports
by Google. The data are based on the location of users and are disaggregated by particular destinations:
grocery and pharmacy, parks, transit stations, retail
and recreation, residential (denoted as “home” in the
figures below), and workplace.

Thus, mobility patterns are, at most, weakly
related to infection rates at the country level.
But how about within the United States? Can we
relate mobility measures to the recent surge of
cases in Arizona, California, Florida, and Texas?
Figure 8 confirms that the surge of U.S. infections
stems from these states. Currently, around 50
percent of daily infections in the country are due
to infections in Arizona, California, Florida, and
Texas. At the end of May, these states accounted
for around 20 percent of the overall cases, while
they now account for more than half of new daily
national cases.

Figures 2-7 plot time series for the regional time allocation for five categories: time spent at home, time
spent at retail and recreation, time spent at grocery
and pharmacy, time spent at parks, and time spent at
work. (Note that adding up all these categories does
not necessarily exhaust the amount of available time
in a day as some activities may not be documented,
such as being outdoors but not in a location included
in the categories Google follows). Although the
United States, unlike Europe, has experienced a rise
in confirmed infections during the past month, the
overall U.S. mobility data do not show any significant
divergence from past trends or relative to Europe.
If anything, inhabitants of European countries have
been reducing time spent at home at a faster rate
than the U.S. population during the past month and
have been increasing time spent at retail, groceries,
and work at a faster rate. The main difference between the United States and Europe is in the overall
level of the decrease in mobility. Visits to retail and
grocery establishments declined substantially less
in the United States than in Europe during the first
months. But all measures have been converging as
of June. Adding to the puzzle, both Asia and South

But once more, our mobility data do not indicate
that residents in these four states spent more
time outdoors than U.S. residents as a whole.
As seen in Figures 9-13, the time spent at home
is on the same decreasing trajectory as in the
United States overall. Time spent at parks has not
bounced back as fast, maybe due to landscape
or weather in these states. And time spent at
workplaces, retail and recreation, and grocery
and pharmacy features broadly the same pattern
as the country as a whole.
A potential explanation for the rise in cases in
these states relative to the United States is the
increase in the number of tests. For a given
number of infected people, an increase in the
share of tests in a location implies an increase in
the share of confirmed infections of that location
relative to the country. Figure 14 shows the share
of daily total U.S. tests performed in Arizona,
California, Florida, and Texas using data from the

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Institute for Health Metrics and Evaluation. This share
increased 5 percentage points in June. But as seen in
Figure 8, the share of daily confirmed cases in these
states increased in June by 30 percentage points
(from 20 percent to 50 percent). Therefore, the relative increase in testing cannot by itself account for
the recent increase of daily infections in these four
states.
Some Final Remarks
We have found that mobility measures are weakly
related to the number of daily infections, both across
regions at a global scale and across U.S. states, and
that the increased number of tests seems to account for only a small part of the regional differences
within the United States. Some additional remarks
are in order. First, a broad, aggregated analysis of
time allocation across regions does not take into account the ability to move within a region. For example, it is harder to travel without restrictions across
subregions in Europe than it is in the United States.
Although Europe and the United States are roughly
of the same geographical size, Europe consists of
numerous countries (36 in our sample) that are able
to close their borders to travelers. This means that
a European citizen can travel without restrictions
within a land area 36 times smaller than a U.S. citizen.
If traveling contributes to spreading the virus, the
United States is in a far worse position than Europe.

Marios Karabarbounis is an economist, Matthew Murphy is a research analyst, and Nicholas
Trachter is a senior economist in the Research
Department at the Federal Reserve Bank of
Richmond.
This article may be photocopied or reprinted
in its entirety. Please credit the authors, source,
and the Federal Reserve Bank of Richmond and
include the italicized statement below.
Views expressed in this article are those of the
authors and not necessarily those of the Federal
Reserve Bank of Richmond or the Federal Reserve
System.

Second, there is a distinction between the time spent
outdoors and the effectiveness of social distancing.
The ability to engage in effective social distancing
outdoors often depends on the city structure (spacious versus crowded workplaces and shopping
stores, reliance on public transportation, etc.), as
well as residents’ willingness to engage in preventive
activities such as wearing face coverings in public
spaces or maintaining physical distance from others.
It would be interesting to quantify these channels in
future work and estimate their impact on regional
differences on infection rates.

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Figure 1: Daily Confirmed COVID-19 Infections

Figure 2: Daily COVID-19 Deaths

6

100
Daily Deaths
Per 1,000,000 People

Daily Confirmed Infec�ons
Per 1,000,000 People

125

75
50
25
0

5
4
3
2
1
0

3/2

3/23

Asia (excludes China)

4/13
Europe

5/4

5/25

South America

6/15

3/2

3/23

Asia (excludes China)

United States

4/13

5/4

Europe

South America

5/25

6/15
United States

Note: The number of daily deaths is calculated as a trailing 7-day average.
Sources: Johns Hopkins Coronavirus Resource Center and Google Sta�s�cs

Figure 3: Change in Time Spent at Home

Figure 4: Change in Time Spent at Retail and Recreation

30

Average Percent Change Rela�ve to
March 2

Average Percent Change Rela�ve to
March 2

Note: The number of daily infec�ons is calculated as a trailing 7-day average.
Sources: Johns Hopkins Coronavirus Resource Center and Google Sta�s�cs

25
20
15
10
5
0
-5

3/2

3/23

Asia (excludes China)

4/13
Europe

Source: Google Community Mobility Reports

5/4

5/25

South America

6/15
United States

10
0
-10
-20
-30
-40
-50
-60
-70
-80

3/2

3/23

Asia (excludes China)

4/13
Europe

5/4

5/25

South America

6/15
United States

Source: Google Community Mobility Reports

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Figure 6: Change in Time Spent at Parks

20

Average Percent Change Rela�ve to
March 2

10
0
-10
-20
-30
-40
-50
-60

3/2

3/23

Asia (excludes China)

4/13
Europe

5/4

5/25

South America

6/15
United States

Source: Google Community Mobility Reports

40
20
0
-20
-40
-60

3/2

3/23

Asia (excludes China)

4/13

5/4

Europe

5/25

South America

6/15
United States

Figure 8: Confirmed COVID-19 Cases,
United States vs. AZ, CA, FL, and TX

10

35,000

0

0.5

30,000

-10

Average Daily Cases

Average Percent Change Rela�ve to
March 2

60

Source: Google Community Mobility Reports

Figure 7: Change in Time Spent at Workplaces

-20
-30
-40
-50
-60

0.4

25,000
20,000

0.3

15,000

0.2

10,000

0.1

5,000

-70
-80

80

3/2

3/23

Asia (excludes China)

4/13
Europe

Source: Google Community Mobility Reports

5/4

5/25

South America

6/15
United States

0

Frac�on of Cases

Average Percent Change Rela�ve to
March 2

Figure 5: Change in Time Spent at Grocery/Pharmacy

3/2

3/23

United States

4/13

5/4

AZ+CA+FL+TX

5/25

6/15

0

Frac�on of Cases (right axis)

Sources: Johns Hopkins Coronavirus Resource Center and Google Sta�s�cs

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Figure 10: Change in Time Spent at Retail/Recreation,
United States vs. AZ, CA, FL, and TX

25

Average Percent Change Rela�ve to
March 2

Average Percent Change
Rela�ve
Axis
Title to March 2

Figure 9: Change in Time Spent at Home,
United States vs. AZ, CA, FL, and TX

20
15
10
5
0
-5

3/2

3/23

4/13
United States

5/4

5/25

6/15

Average Percent Change Rela�ve to
March 2

Average Percent Change Rela�ve to
March 2

United States
Source: Google Community Mobility Reports

-30
-40
-50
-60

3/2

3/23

4/13

5/4

5/25

6/15

AZ+CA+FL+TX

Figure 12: Change in Time Spent at Parks,
United States vs. AZ, CA, FL, and TX

10
5
0
-5

4/13

-20

Source: Google Community Mobility Reports

15

3/23

-10

United States

Figure 11: Change in Time Spent at Grocery/Pharmacy,
United States vs. AZ, CA, FL, and TX

3/2

0

AZ+CA+FL+TX

Source: Google Community Mobility Reports

-10
-15
-20
-25
-30
-35

10

5/4

5/25

AZ+CA+FL+TX

6/15

60
40
20
0
-20
-40
-60

3/2

3/23

4/13

United States

5/4

5/25

6/15

AZ+CA+FL+TX

Source: Google Community Mobility Reports

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Figure 14: Fraction of U.S. COVID-19 Tests Administered in
AZ, CA, FL, and TX

0
0.30

-10
-20
-30
-40
-50
-60

3/2

3/23

4/13

United States

5/4

5/25

6/15

AZ+CA+FL+TX

Source: Google Community Mobility Reports

Frac�on of Total U.S. Covid-19 Tests
in AZ, CA, FL, and TX

Average Percent Change Rela�ve to
March 2

Figure 13: Change in Time Spent at Workplaces,
United States vs. AZ, CA, FL, and TX

0.25

0.20

0.15

0.10

3/2

3/23

4/13

5/4

5/25

6/15

Source: Ins�tute for Health Metrics and Evalua�on

List of Countries Included in Our Sample
by Region:
Asia: India, Indonesia, Pakistan, Bangladesh, Japan,
Philippines, Vietnam, Turkey, Thailand, Myanmar (formerly Burma), South Korea, Iraq, Afghanistan, Saudi
Arabia, Malaysia, Yemen, Nepal, Taiwan, Sri Lanka,
Kazakhstan, Cambodia, Jordan, United Arab Emirates, Tajikistan, Israel, Hong Kong, Laos, Kyrgyzstan,
Singapore, Oman, Kuwait, Georgia, Mongolia, Qatar,
Bahrain
Europe: Russia, Germany, United Kingdom, France,
Italy, Spain, Ukraine, Poland, Romania, Netherlands,
Belgium, Czech Republic, Greece, Portugal, Sweden,
Hungary, Belarus, Austria, Serbia, Switzerland, Bulgaria, Denmark, Finland, Slovakia, Norway, Ireland,
Croatia, Moldova, Bosnia and Herzegovina, Estonia,
Lithuania, North Macedonia, Slovenia, Latvia, Luxembourg, Malta
South America: Brazil, Colombia, Argentina, Peru, Venezuela, Chile, Ecuador, Bolivia, Paraguay, Uruguay

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