World
Inequality
ReportExecutive Summary
English version

Coordinated byFacundo Alvaredo  
Lucas Chancel  
Thomas Piketty
Emmanuel Saez  Gabriel Zucman

Written and coordinated by:Facundo Alvaredo
Lucas Chancel
Thomas Piketty
Emmanuel Saez
Gabriel Zucman
General coordinator:
Lucas Chancel

Report research team:Thomas Blanchet
Richard Clarke
Leo Czajka
Luis Estévez-Bauluz
Amory Gethin
Wouter Leenders

Creative Commons Licence
4.0 - CC BY-NC-SA 4.0
World Inequality Lab, 2017
Design: Grand Krü, Berlin
Cover artwork based on a
photograph by Dimitri
Vervitsiotis / Getty Images

This report emphasizes recent
research articles written by:
Facundo Alvaredo
Lydia Assouad
Anthony B. Atkinson
Charlotte Bartels
Thomas Blanchet
Lucas Chancel
Luis Estévez-Bauluz
Juliette Fournier
Bertrand Garbinti
Jonathan Goupille-Lebret
Clara Martinez-Toledano
Salvatore Morelli
Marc Morgan
Delphine Nougayrède
Filip Novokmet
Thomas Piketty
Emmanuel Saez
Li Yang
Gabriel Zucman

WID.world fellows:
The report ultimately relies on the data collection,
production and harmonization work carried out
by more than a hundred WID.world fellows
located over five continents and contributing to
the World Wealth and Income Database (visit
www.wid.world/team for more information).
Analyses presented in the report reflect theviews of the report’s editors and not necessarily
those of WID.world fellows.

World Inequality Report  2018
Executive Summary

Executive Summary

I. What is the aim of theWorld Inequality Report 2018?
The World Inequality Report 2018 relies on a cutting-edge methodology tomeasure income and wealth inequality in a systematic and transparent manner.
By developing this report, the World Inequality Lab seeks to fill a democratic
gap and to equip various actors of society with the necessary facts to engage in
informed public debates on inequality.
▶▶ The objective of the World Inequality Report2018 is to contribute to a more informed global
democratic debate on economic inequality bybringing the latest and most complete data to
the public discussion.

detailed and consistent income and wealthinequality statistics. Standard measures ofinequality often rely on household surveys,
which routinely underestimate the income
and wealth of individuals at the top of thesocial ladder.

▶▶ Economic inequality is widespread andto some extent inevitable. It is our belief,
however, that if rising inequality is not properly monitored and addressed, it can lead tovarious sorts of political, economic, and social
catastrophes.
▶▶ Our objective is not to bring everyone

into agreement regarding inequality; this will
never happen, for the simple reason that no
single scientific truth exists about the ideal
level of inequality, let alone the most sociallydesirable mix of policies and institutions toachieve this level. Ultimately, it is up to publicdeliberation, and political institutions andtheir processes to make these difficult decisions. But this deliberative process requires
more rigorous and transparent information
on income and wealth.
▶▶ To equip citizens to make such decisions,

we also seek to relate macroeconomic
phenomenon—such as nationalization andprivatization policies, capital accumulation,and the evolution of public debt—to microeconomic trends in inequality focused on individuals’ earnings and government transfers,
personal wealth, and debt.
▶▶ Reconciling macro and microeconomic

inequality data is not a straightforward
exercise given that many countries do not
publicly release, or may not even produce,

4

World Inequalit y Report  2018▶▶ To overcome current limitations, we rely

on a groundbreaking methodology which
combines in a systematic and transparent
manner all data sources at our disposal:
national income and wealth accounts(including, when possible, offshore wealthestimates); household income and wealthsurveys; fiscal data coming from taxes on
income; inheritance and wealth data (whenthey exist); and wealth rankings.
▶▶The series presented in this report relyon the collective efforts of more than ahundred researchers, covering all continents, who contribute to the WID.world
database. All the data are available online
on wir2018.wid.world and are fully reproducible, allowing anyone to perform theirown analysis and make up their own mind
about inequality.

Executive Summary

II. What are our new findings on global
income inequality?
We show that income inequality has increased in nearly all world regions inrecent decades, but at different speeds. The fact that inequality levels are so
different among countries, even when countries share similar levels of development, highlights the important roles that national policies and institutions playin shaping inequality.
Income inequality varies greatly acrossworld regions. It is lowest in Europe
and highest in the Middle East.
▶▶ Inequality within world regions varies
greatly. In 2016, the share of total national
income accounted for by just that nation’s
top 10% earners (top 10% income share)
was 37% in Europe, 41% in China, 46% in
Russia, 47% in US-Canada, and around
55% in sub-Saharan Africa, Brazil, andIndia. In the Middle East, the world’s mostunequal region according to our estimates,
the top 10% capture 61% of national income(Figure E1).

In recent decades, income inequality
has increased in nearly all countries,
but at different speeds, suggestingthat institutions and policies matter inshaping inequality.
▶▶ Since 1980, income inequality has
increased rapidly in North America, China,
India, and Russia. Inequality has grownmoderately in Europe (Figure E2a). From a
broad historical perspective, this increase ininequality marks the end of a postwar egalitarian regime which took different forms inthese regions.

Figure E1
Top 10% national income share across the world, 2016
70%

61%
Share of national income (%)

60%
50%

54%

55%

55%

SubSaharanAfricaBrazil

India

47%

46%
41%

40%

37%

30%
20%
10%
0%
EuropeChina

RussiaUS-Canada

Middle East

Source: WID.world (2017). See wir2018.wid.world for data series and notes.

In 2016, 37% of national income was received by the Top 10% in Europe against 61% in the Middle-East.

World Inequalit y Report  2018

5

Executive Summary

Figure E2a
Top 10% income shares across the world, 1980–2016: Rising inequality almost everywhere,
but at different speeds
60%

Share of national income (%)

India
US-Canada

50%

RussiaChina
40%

Europe

30%

20%

1980

1985

1990

1995

2000

2005

2010

2015

Source: WID.world (2017). See wir2018.wid.world for data series and notes.

In 2016, 47% of national income was received by the top 10% in US-Canada, compared to 34% in 1980.

▶▶ There are exceptions to the general

pattern. In the Middle East, sub-SaharanAfrica, and Brazil, income inequality hasremained relatively stable, at extremely
high levels (Figure E2b). Having never gone
through the postwar egalitarian regime, theseregions set the world “inequality frontier.”▶▶ The diversity of trends observed acrosscountries since 1980 shows that income
inequality dynamics are shaped by a varietyof national, institutional and political contexts.
▶▶ This is illustrated by the different trajec-

tories followed by the former communist
or highly regulated countries, China, India,
and Russia (Figure E2a and b). The rise ininequality was particularly abrupt in Russia,
moderate in China, and relatively gradual in
India, reflecting different types of deregulation and opening-up policies pursued over the
past decades in these countries.
▶▶ The divergence in inequality levels has been

particularly extreme between Western Europe

6World Inequalit y Report  2018

and the United States, which had similar levels
of inequality in 1980 but today are in radicallydifferent situations. While the top 1% income
share was close to 10% in both regions in 1980,
it rose only slightly to 12% in 2016 in Western
Europe while it shot up to 20% in the UnitedStates. Meanwhile, in the United States, thebottom 50% income share decreased from morethan 20% in 1980 to 13% in 2016 (Figure E3).
▶▶ The income-inequality trajectory observedin the United States is largely due to massive
educational inequalities, combined with a tax
system that grew less progressive despite
a surge in top labor compensation sincethe 1980s, and in top capital incomes in
the 2000s. Continental Europe meanwhile
saw a lesser decline in its tax progressivity,
while wage inequality was also moderated
by educational and wage-setting policies
that were relatively more favorable to lowand middle-income groups. In both regions,income inequality between men and womenhas declined but remains particularly strongat the top of the distribution.

Executive Summary

Figure E2b
Top 10% income shares across the world, 1980–2016: Is world inequality moving towards thehigh-inequality frontier?

Share of national income (%)

70%

Middle East

60%

India
Brazil50%

Sub-SaharanAfrica40%

US-Canada
Russia30%

ChinaEurope

20%
1980

1985

1990

1995

2000

2005

2010

2015

Source: WID.world (2017). See wir2018.wid.world for data series and notes.

In 2016, 55% of national income was received by the Top 10% earners in India, against 31% in 1980.

How has inequality evolved in recent decades among global citizens? We provide the first estimates of how the growth in global income since 1980 has been
distributed across the totality of the world population. The global top 1% earners
has captured twice as much of that growth as the 50% poorest individuals. The
bottom 50% has nevertheless enjoyed important growth rates. The global middle class (which contains all of the poorest 90% income groups in the EU and theUnited States) has been squeezed.
At the global level, inequality has risen
sharply since 1980, despite strong
growth in China.
▶▶ The poorest half of the global population has seen its income grow significantly
thanks to high growth in Asia (particularly
in China and India). However, becauseof high and rising inequality within countries, the top 1% richest individuals in
the world captured twice as much growth
as the bottom 50% individuals since1980 ( Figure E4 ). Income growth has
been sluggish or even zero for individuals
with incomes between the global bottom
50% and top 1% groups. This includes all

North American and European lower- andmiddle-income groups.
▶▶ The rise of global inequality has not beensteady. While the global top 1% income share
increased from 16% in 1980 to 22% in 2000,
it declined slightly thereafter to 20%. The
income share of the global bottom 50% has
oscillated around 9% since 1980 (Figure E5).
The trend break after 2000 is due to a reduction in between-country average income
inequality, as within-country inequality has
continued to increase.

World Inequalit y Report  20187

Executive Summary

Figure E3
Top 1% vs. Bottom 50% national income shares in the US and Western Europe, 1980–2016:
Diverging income inequality trajectories
US
22%

Share of national income (%)

20%

18%

Top 1% US

16%

14%

12%

Bottom 50%
US

10%
1980

1985

1990

1995

2000

2005

2010

2015

Source: WID.world (2017). See wir2018.wid.world for data series and notes.

In 2016, 12% of national income was received by the top 1% in Western Europe, compared to 20% in the United States. In 1980, 10% of national
income was received by the top 1% in Western Europe, compared to 11% in the United States.

Western Europe
24%

Share of national income (%)

22%
Bottom 50%
Western Europe

20%
18%
16%
14%
12%

Top 1%
Western Europe

10%
8%
1980

1985

1990

1995

2000

Source: WID.world (2017). See wir2018.wid.world for data series and notes.

In 2016, 22% of national income was received by the Bottom 50% in Western Europe.

8

World Inequalit y Report  2018

2005

2010

2015

Executive Summary

Figure E4
The elephant curve of global inequality and growth, 1980–2016

Real income growth per adult (%)

250%

Bottom 50%
captured 12%of total growth

Top 1%
captured 27%
of total growth

200%
Prosperity of
the global 1%

150%

100%
Rise of emerging
countries

Squeezed bottom 90%
in the US & Western Europe

50%

0%
10

20

30

40

50

60

70

80

90

99

99.9

99.99 99.999

Income group (percentile)
Source: WID.world (2017). See wir2018.wid.world for more details.

On the horizontal axis, the world population is divided into a hundred groups of equal population size and sorted in ascending order from left toright, according to each group's income level. The Top 1% group is divided into ten groups, the richest of these groups is also divided into tengroups, and the very top group is again divided into ten groups of equal population size. The vertical axis shows the total income growth of an
average individual in each group between 1980 and 2016. For percentile group p99p99.1 (the poorest 10% among the world's richest 1%), growth
was 74% between 1980 and 2016. The Top 1% captured 27% of total growth over this period. Income estimates account for differences in the costof living between countries. Values are net of inﬂation.

Figure E5
The rise of the global top 1% versus the stagnation of the global bottom 50%, 1980–2016
25%

Share of global income (%)

Global Top 1%
20%

15%

Global Bottom 50%
10%

5%
1980

1985

1990

1995

2000

2005

2010

2015

Source: WID.world (2017). See wir2018.wid.world for data series and notes.

In 2016, 22% of global income was received by the Top 1% against 10% for the Bottom 50%. In 1980, 16% of global income was received by theTop 1% against 8% for the Bottom 50%.

World Inequalit y Report  20189

Executive Summary

III. Why does the evolution of private
and public capital ownership matterfor inequality?
Economic inequality is largely driven by the unequal ownership of capital, which
can be either privately or public owned. We show that since 1980, very largetransfers of public to private wealth occurred in nearly all countries, whether
rich or emerging. While national wealth has substantially increased, public
wealth is now negative or close to zero in rich countries. Arguably this limits theability of governments to tackle inequality; certainly, it has important implications for wealth inequality among individuals.
Over the past decades, countries havebecome richer but governments havebecome poor.

▶▶ The ratio of net private wealth to net

national income gives insight into the total
value of wealth commanded by individuals in

Figure E6
The rise of private capital and the fall of public capital in rich countries, 1970–2016

Value of net public and private wealth (% of national income)

800%
700%

Private capital
Spain

600%

UK
Japan

500%

FranceUS

400%

Germany
300%
200%
Public capital
100%
0%
-100%
1970

1975

1980

1985

1990

1995

2000

2005

2010

2015

Source: WID.world (2017). See wir2018.wid.world for data series and notes.

In 2015, the value of net public wealth (or public capital) in the US was negative (-17% of net national income) while the value of net private wealth(or private capital) was 500% of national income. In 1970, net public wealth amounted to 36% of national income while the ﬁgure was 326% for net
private wealth. Net private wealth is equal to new private assets minus net private debt. Net public wealth is equal to public assets minus public debt.

10

World Inequalit y Report  2018

Executive Summary

a country, as compared to the public wealthheld by governments. The sum of private andpublic wealth is equal to national wealth. Thebalance between private and public wealth isa crucial determinant of the level of inequality.
▶▶ There has been a general rise in net private

wealth in recent decades, from 200–350%
of national income in most rich countries in1970 to 400–700% today. This was largely
unaffected by the 2008 financial crisis, or by
the asset price bubbles seen in some countries such as Japan and Spain (Figure E6). In
China and Russia there have been unusuallylarge increases in private wealth; following
their transitions from communist- to capitalist-oriented economies, they saw it
quadruple and triple, respectively. Private

wealth–income ratios in these countries areapproaching levels observed in France, theUK, and the United States.
▶▶ Conversely, net public wealth (that is, public

assets minus public debts) has declined in nearly
all countries since the 1980s. In China andRussia, public wealth declined from 60–70%
of national wealth to 20–30%. Net public
wealth has even become negative in recent
years in the United States and the UK, and is
only slightly positive in Japan, Germany, andFrance (Figure E7). This arguably limits government ability to regulate the economy, redistribute income, and mitigate rising inequality.
The only exceptions to the general decline inpublic property are oil-rich countries with large
sovereign wealth funds, such as Norway.

Value of net public wealth (% of national wealth)Figure E7
The decline of public capital, 1970–2016
70%
60%
50%

China
France40%

Germany
30%

Japan
UK

20%

US

10%
0%
-10%
1978

1983

1988

1993

1998

2003

2008

2013

Source: WID.world (2017). See wir2018.wid.world for data series and notes.

In 2015, the share of public wealth in national wealth in France was 3%, compared to 17% in 1980.

World Inequalit y Report  201811

Executive Summary

IV. What are our new findings on
global wealth inequality?
The combination of large privatizations and increasing income inequality withincountries has fueled the rise of wealth inequality among individuals. In Russia
and the United States, the rise in wealth inequality has been extreme, whereas inEurope it has been more moderate. Wealth inequality has not yet returned to its
extremely high early-twentieth-century level in rich countries.
Wealth inequality among individuals
has increased at different speeds
across countries since 1980.
▶▶ Increasing income inequality and the largetransfers of public to private wealth occurring
over the past forty years have yielded rising
wealth inequality among individuals. Wealthinequality has not, however, yet reached its
early-twentieth-century levels in Europe orin the United States.
▶▶ The rise in wealth inequality has nonethe-less been very large in the United States,
where the top 1% wealth share rose from
22% in 1980 to 39% in 2014. Most of that
increase in inequality was due to the rise of

the top 0.1% wealth owners. The increase in
top-wealth shares in France and the UK was
more moderate over the past forty years,
in part due to the dampening effect of therising housing wealth of the middle class, anda lower level of income inequality than the
United States’ (Figure E8).
▶▶ Large rises in top-wealth shares havealso been experienced in China andRussia following their transitions from
communism to more capitalist economies.
The top 1% wealth share doubled in both
China and Russia between 1995 and 2015,
from 15% to 30% and from 22% to 43%,
respectively.

Figure E880%
Top 1% wealth shares across the world, 1913–2015: the fall and rise of personal wealth inequality

Share of personal wealth (%)

70%
China

60%

FranceRussia

50%

UK

40%

US

30%
20%
10%
0%
1920

1930

1940

1950

1960

Source: WID.world (2017). See wir2018.wid.world for data series and notes.

In 2015, the Top 1% wealth share was 43% in Russia against 22% in 1995.

12

World Inequalit y Report  2018

1970

1980

1990

2000

2010

Executive Summary

V. What is the future of global
inequality and how should it
be tackled?
We project income and wealth inequality up to 2050 under different scenarios.
In a future in which “business as usual” continues, global inequality will ­f urther
increase. Alternatively, if in the coming decades all countries follow the moderate inequality trajectory of Europe over the past decades, global income­inequality can be reduced—in which case there can also be substantial progressin eradicating global poverty.
The global wealth middle class will besqueezed under “business as usual.”▶▶ Rising wealth inequality within countries
has helped to spur increases in global wealthinequality. If we assume the world trend tobe captured by the combined experience ofChina, Europe and the United States, thewealth share of the world’s top 1% wealthiest people increased from 28% to 33%,
while the share commanded by the bottom

75% oscillated around 10% between 1980
and 2016.
▶▶ The continuation of past wealth-inequality

trends will see the wealth share of the top
0.1% global wealth owners (in a world represented by China, the EU, and the UnitedStates) catch up with the share of the global
wealth middle class by 2050 (Figure E9).

Figure E9
The squeezed global wealth middle class, 1980–2050
40%

Share of global wealth (%)

Top 1%

30%
Middle 40%“Global middle class”
20%
Top 0.1%

10%
Assuming“business as usual”

Top 0.01%
0%
1980

1990

2000

2010

2020

2030

2040

2050

Source: WID.world (2017). See wir2018.wid.world for data series and notes.

In 2016, in a world represented by China, Europe and the US, the global wealth share of the Top 1% was 33%. Under "Business as usual", the Top
1% global wealth share would reach 39% by 2050, while the Top 0.1% wealth owners would own nearly as much wealth (26%) as the middle class(27%). The evolution of global wealth groups from 1987 to 2017 is represented by China, Europe and the US. Values are net of inﬂation.

World Inequalit y Report  201813

Executive Summary

Figure E10
Rising global income inequality is not inevitable in the future
30%

Share of global income (%)

25%… all countries follow US’s
1980–2016 inequality
trend = scenario 2

Global Top 1%
income share… all countries follow theirown 1980–2016 inequality
trend = scenario 1

20%… all countries follow EU
1980–2016 inequality
trend = scenario 3

Global inequality
assuming …

15%

scenario 3

10%

5%

0%
1980

scenario 1
scenario 2

Global Bottom 50%
income share

1990

2000

2010

2020

2030

2040

2050

Source: WID.world (2017). See wir2018.wid.world for data series and notes.

If all countries follow the inequality trajectory of the US between 1980 and 2016 from 2017 to 2050, the income share of the global Top 1% willreach 28% by 2050. Income share estimates are calculated using Purchasing Power Parity (PPP) euros. PPP accounts for differences in the cost ofliving between countries. Values are net of inﬂation.

Global income inequality will also
increase under a “business as usual”
scenario, even with optimistic growth
assumptions in emerging countries.
This is not inevitable, however.
▶▶ Global income inequality will also increase
if countries prolong the income inequality
path they have been on since 1980—even
with relatively high income growth predictions in Africa, Latin America, and Asia inthe coming three decades. Global income
inequality will increase even more if all
countries follow the high-inequality trajectory followed by the United States between

14

World Inequalit y Report  20181980 and 2016. However, global inequality
will decrease moderately if all countries
follow the inequality trajectory followed by
the EU between 1980 and today (Figure E10).
▶▶ Within-country inequality dynamics

have a tremendous impact on the eradication of global poverty. Depending on which
inequality trajectory is followed by countries,
the incomes of the bottom half of the world
population may vary by factor of two by 2050
(Figure E11), ranging from €4 500 to € 9100
per year, per adult.

Executive Summary

Figure E11
Inequality has substantial impacts on global poverty€10 000… all countries follow
EU 1980–2016
inequality trend

Annual income per adult (€)€9 100
Average income
assuming …

€8 000€6 300… all countries prolonge
their own 1980–2016
inequality trend€6 000Bottom 50% average income€4 500€4 000… all countries follow
US 1980-2016
inequality trend€3 100€2 000€1 600
€0
1980

1990

2000

2010

2020

2030

2040

2050

Source: WID.world (2017). See wir2018.wid.world for data series and notes.

If all countries follow the inequality trajectory of Europe between 1980 and 2016, the average income of the Bottom 50% of the world population will be€9 100 by 2050. Income estimates are calculated using Purchasing Power Parity (PPP) euros. For comparison, €1 = $1.3 = ¥4.4 at PPP. PPP
accounts for differences in the cost of living between countries. Values are net of inﬂation.

Tackling global income and wealth inequality requires important shifts in­national and global tax policies. Educational policies, corporate governance,
and wage-setting policies need to be reassessed in many countries. Data transparency is also key.

Tax progressivity is a proven tool
to combat rising income and wealthinequality at the top.
▶▶ Research has demonstrated that tax
progressivity is an effective tool to combat
inequality. Progressive tax rates do not only
reduce post-tax inequality, they also diminish
pre-tax inequality by giving top earners lessincentive to capture higher shares of growth
via aggressive bargaining for pay rises andwealth accumulation. Tax progressivity was
sharply reduced in rich and some emerging
countries from the 1970s to the mid-2000s.
Since the global financial crisis of 2008, thedownward trend has leveled off and evenreversed in certain countries, but future

evolutions remain uncertain and will dependon democratic deliberations. It is also worth
noting that inheritance taxes are nonexistentor near zero in high-inequality emerging
countries, leaving space for important tax
reforms in these countries.
A global financial register recording
the ownership of financial assets
would deal severe blows to tax
evasion, money laundering, and risinginequality.
▶▶ Although the tax system is a crucial tool
for tackling inequality, it also faces potential obstacles. Tax evasion ranks high among
these, as recently illustrated by the ParadiseWorld Inequalit y Report  201815

Executive Summary

Papers revelations. The wealth held in tax
havens has increased considerably since the1970s and currently represents more than
10% of global GDP. The rise of tax havens
makes it difficult to properly measure andtax wealth and capital income in a globalized
world. While land and real-estate registries
have existed for centuries, they miss a large
fraction of the wealth held by households
today, as wealth increasingly takes the form offinancial securities. Several technical options
exist for creating a global financial register,which could be used by national tax authorities to effectively combat fraud.
More equal access to education andwell-paying jobs is key to addressing
the stagnating or sluggish income
growth rates of the poorest half of the
population.
▶▶ Recent research shows that there canbe an enormous gap between the public
discourse about equal opportunity andthe reality of unequal access to education.
In the United States, for instance, out of ahundred children whose parents are among
the bottom 10% of income earners, only
twenty to thirty go to college. However,that figure reaches ninety when parents arewithin the top 10% earners. On the positiveside, research shows that elite colleges who
improve openness to students from poor
backgrounds need not compromise their

16

World Inequalit y Report  2018

outcomes to do so. In both rich and emerging
countries, it might be necessary to set transparent and verifiable objectives—while alsochanging financing and admission systems—
to enable equal access to education.
▶▶ Democratic access to education canachieve much, but without mechanisms
to ensure that people at the bottom of the
distribution have access to well-paying jobs,
education will not prove sufficient to tackle
inequality. Better representation of workers
in corporate governance bodies, and healthy
minimum-wage rates, are important tools toachieve this.
Governments need to invest in the
future to address current income andwealth inequality levels, and to prevent
further increases in them.
▶▶ Public investments are needed in education, health, and environmental protection
both to tackle existing inequality and toprevent further increases. This is particularly difficult, however, given that governments in rich countries have become poorand largely indebted. Reducing public debt isby no means an easy task, but several options
to accomplish it exist—including wealth taxation, debt relief, and inflation— and have beenused throughout history when governments
were highly indebted, to empower younger
generations.

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