Draw and interpret a Lorenz curve, identifying perfect equality, perfect inequality, and real distributions
Calculate and interpret the Gini coefficient as a measure of inequality
Distinguish between income inequality and wealth inequality, and explain why wealth inequality is greater
Apply UK Gini data and the Oxfam 2023 report to evaluate causes and consequences of inequality
Income vs Wealth
Income vs Wealth: What's the Difference?
Key Distinction
INCOME is a flow — the money received per period (wages, rent, dividends, benefits). WEALTH is a stock — the value of assets owned minus liabilities (property, savings, shares, pension funds). Wealth inequality is almost always more extreme than income inequality because: wealth accumulates over time; wealth generates more income (returns on capital); inheritance concentrates wealth across generations.
UK INCOME INEQUALITY
UK Gini for income: 0.36 (post-tax, ONS 2022). Top 20% earn ~5× more than bottom 20%. Richest 10% hold 28% of total income. More equal than US (0.40) but less equal than Nordics (0.28).
UK WEALTH INEQUALITY
UK Gini for wealth: ~0.62 (ONS Wealth & Assets Survey). Richest 10% hold 43% of all wealth; bottom 50% hold only 9%. Top 1% hold ~23% of total wealth. Wealth inequality is nearly double income inequality.
WHY THE GAP?
Returns on capital compound over time. £100,000 invested at 5%/year = £432,000 in 30 years (without adding anything). Inheritances pass concentrated wealth to next generation. Owner-occupied housing appreciated dramatically 2000–2023.
The further the Lorenz curve bows below the diagonal, the more unequal the distribution. At any point on the x-axis (e.g. 40% of population), read up to the Lorenz curve to find what % of income that group earns. If the bottom 40% earn 15% of income (not 40%), inequality is high.
GINI COEFFICIENT
Gini = Area A / (A + B). Range: 0 = perfect equality (Lorenz = diagonal, A=0); 1 = perfect inequality (one person has everything, A = maximum). A higher Gini = more unequal. UK income Gini ≈ 0.36; UK wealth Gini ≈ 0.62; South Africa ≈ 0.63; Sweden ≈ 0.27.
PERFECT EQUALITY vs INEQUALITY
Perfect equality: Lorenz curve = diagonal. Perfect inequality: Lorenz curve hugs the x-axis all the way to 100%, then jumps to 100% income — one person has everything.
Causes of Inequality
Why Does Inequality Exist?
LABOUR MARKET
Wage differentials from MRP differences, human capital, discrimination, and monopsony create income inequality. Rise in skilled-labour premium since 1980s due to skill-biased technical change (computers, AI). Decline in trade union membership removed wage compression. CEO pay vs worker pay ratio rose from ~20× to 100×+.
WEALTH ACCUMULATION
Returns on capital compound over time. Those who own assets (property, stocks, pensions) see wealth grow faster than wages. UK house prices rose ~300% in real terms 1985–2023. Inheritance transfers concentrated wealth across generations — 1 in 5 UK adults expect to inherit more than £100,000.
GLOBALISATION
Increased demand for high-skilled workers in developed countries (comparative advantage in skilled industries). Simultaneously, increased competition for low-skilled workers (from lower-wage countries) suppresses low-end wages. Result: widening within-country inequality.
GOVERNMENT POLICY
Thatcher-era policies (1979–97): privatisation, deregulation, union reforms, top tax rate cut from 83% to 40% — all contributed to rising Gini. Post-2008 QE boosted asset prices, benefiting wealthy disproportionately. Austerity (2010–19) reduced redistributive welfare spending. These policy choices significantly shaped current inequality.
Real-World Application · UK QE
UK Gini & Quantitative Easing
💷 WHAT IS QE?
Quantitative Easing (QE): the Bank of England created digital money (£895bn between 2009 and 2021) to buy government bonds and other financial assets. This pushed up the prices of financial assets (bonds, equities) and lowered long-term interest rates, stimulating borrowing and investment. It was the main macroeconomic policy tool post-2008 financial crisis.
📊 THE DISTRIBUTIONAL EFFECT
Bank of England (2012) estimated that QE boosted the wealth of the richest 10% by ~£128,000 each — because they own most of the financial assets that QE inflated. Households in the bottom 50% (with little savings or investments) saw negligible wealth gains. House prices also rose as interest rates fell — benefiting homeowners (disproportionately older, wealthier) over renters.
📈 GINI IMPACT
While QE reduced income inequality slightly (by avoiding a deeper recession), it significantly widened wealth inequality. The Lorenz curve for wealth shifted further from the diagonal during the QE era. This illustrates a key point: income and wealth Gini can move in opposite directions, and macro policy can have profound distributional consequences.
📝 EVALUATION
QE was arguably necessary to prevent a 1930s-style depression — the alternative (mass unemployment, deflating GDP) would have hurt lower-income workers most through job losses. The distributional critique: the benefits were poorly targeted. A "helicopter money" approach (QE directed to households) might have achieved the macro goal more equitably. This is an ongoing academic debate.
Real-World Application · Global Inequality
Oxfam Davos 2023: Global Wealth Divergence
🌍
Oxfam Davos 2023
The world's richest 1% captured nearly twice as much new wealth as the rest of humanity combined in 2020–2022.
THE NUMBERS
During the first 2 years of COVID recovery: global billionaire wealth grew by $3.3 trillion (63% increase). The rest of humanity's combined wealth grew by $1.7 trillion. Elon Musk's wealth alone grew by ~$100bn. Oxfam: a 5% wealth tax on the world's millionaires would raise $1.7 trillion/year — enough to lift 2 billion people out of poverty.
WHY? THE ECONOMICS
COVID accelerated existing trends: (1) Tech sector dominance — the pandemic boosted digital services disproportionately benefiting tech billionaires. (2) Asset price inflation — central bank stimulus (low rates + QE) globally inflated stock markets. (3) Monopsony and labour suppression — many essential workers in low-wage, high-inequality labour markets. (4) K-shaped recovery: high-skill workers thrived (WFH); low-skill workers (hospitality, retail) suffered job losses.
POLICY DEBATE
Oxfam's recommendations: global wealth tax, windfall taxes on excess profits, universal social protection. Criticism: capital flight risks (wealthy move assets to low-tax jurisdictions); practical measurement difficulties; may reduce investment incentives. Counter: countries that maintain equality (Nordics) have higher growth, better health outcomes, and greater social mobility than high-inequality countries (US, UK).
Consequences of Inequality
Why Does Inequality Matter?
ECONOMIC EFFICIENCY
High inequality may reduce aggregate demand (lower-income households have higher marginal propensity to consume — redistribution boosts spending). BUT: some inequality provides incentives for effort, education, and entrepreneurship. Optimal level of inequality is contested.
SOCIAL MOBILITY
High inequality reduces social mobility — children born into low-income families have fewer educational and health opportunities. The "Great Gatsby Curve" (Miles Corak, 2013): countries with higher inequality have lower inter-generational mobility. UK social mobility is below the OECD average.
HEALTH AND WELLBEING
Wilkinson & Pickett (The Spirit Level, 2009): countries with higher inequality have worse outcomes on almost every social measure — mental health, life expectancy, crime, educational attainment, teen pregnancy. The link is not just poverty but relative inequality — people respond to status differences.
POLITICAL STABILITY
Extreme inequality can reduce trust in institutions and fuel political populism. The rise of anti-establishment politics in the UK (Brexit) and US (Trump) has been linked by some economists to wage stagnation and inequality among non-graduate workers. Inequality has externalities beyond individual welfare.
Policy Responses
Policies to Reduce Inequality
PROGRESSIVE TAXATION
Higher marginal tax rates on top incomes redistribute from rich to poor. UK top income tax rate: 45% (over £125,140). Capital Gains Tax, Inheritance Tax, Stamp Duty all reduce wealth concentration. Evaluation: may reduce incentive; risk of tax avoidance; Laffer curve effects uncertain in practice.
BENEFITS AND TRANSFERS
Universal Credit, Housing Benefit, Child Benefit, State Pension. Redistribution via welfare state. UK: benefits reduce income Gini from ~0.52 (market income) to ~0.36 (post-tax-and-transfer income) — a massive compression. Evaluation: dependency risks; work disincentives; fiscal cost.
EDUCATION AND TRAINING
Equalise human capital across income groups. Free school meals, Sure Start, university bursaries, apprenticeships. Long-run approach: raises productive capacity of low-income workers. Most economists consider this the most sustainable tool — targets root cause rather than redistribution of outcomes.
MINIMUM WAGE / WORKERS' RIGHTS
NLW raises wages at the bottom, compressing the distribution. Strengthening collective bargaining. Evaluation: empirically effective in UK (NLW reduced wage inequality at bottom of distribution without significant unemployment effects per Low Pay Commission).
Evaluation
Evaluating the Lorenz Curve & Gini
For (value of measuring inequality)
Lorenz curve and Gini provide a single, comparable measure enabling cross-country and time-series analysis
Clear evidence base for policy: UK Gini rising from 0.25 to 0.36 since 1970s justifies redistributive intervention
Links between inequality and social outcomes (health, crime, mobility) suggest economic case for redistribution beyond pure equity concerns
QE example shows macro policy has distributional consequences — measurement enables accountability
Against (limitations)
Gini condenses entire distribution into one number — two countries can have same Gini with very different distributions
Income Gini misses wealth inequality (far more extreme) and non-monetary wellbeing
Causation vs correlation: the Spirit Level links inequality to bad outcomes, but critics dispute whether inequality causes them or both are caused by other factors
Redistribution policies face trade-off between equality and efficiency — high taxes may reduce incentives (though empirical evidence is contested)
Essay Tip: "The key evaluation: the Gini is useful for comparison but hides the structure of inequality. For AQA exams, always ask: is the inequality rising at the top (CEO pay, asset wealth) or the bottom (poverty, low wages)? Different causes require different policies. Progressive taxation targets top-end inequality; minimum wage targets bottom-end; education targets human capital gaps."
Glossary
Key Terms
Lorenz Curve
A graphical representation of the income (or wealth) distribution. The x-axis shows cumulative % of population; y-axis shows cumulative % of income. The further from the diagonal, the more unequal.
Gini Coefficient
A numerical measure of inequality derived from the Lorenz curve. Gini = Area A / (A+B). Range: 0 (perfect equality) to 1 (perfect inequality). UK income Gini ≈ 0.36.
Line of Perfect Equality
The 45° diagonal on a Lorenz diagram. Represents a distribution where each x% of the population earns exactly x% of income. Gini = 0.
Income Inequality
Unequal distribution of the income flow between households. Measured by income Gini. Partly offset by taxes and transfers (UK market Gini ≈ 0.52 → post-transfer ≈ 0.36).
Wealth Inequality
Unequal distribution of the stock of assets. Always more extreme than income inequality (UK wealth Gini ≈ 0.62). Driven by compound returns, inheritance, and asset price inflation.
Quantitative Easing (QE)
A monetary policy tool where the central bank purchases financial assets to inject money into the economy. Side effect: inflates asset prices, disproportionately benefiting wealthy asset-owners.
Question 1 of 8 · Lorenz Curve & Gini Coefficient
On a Lorenz diagram, a curve closer to the line of perfect equality indicates:
A
Higher inequality — the curve is bowing outward
B
Lower inequality — the distribution is more even
C
Perfect inequality — one person owns everything
D
That the Gini coefficient equals 1
Answer · Question 1
On a Lorenz diagram, a curve closer to the line of perfect equality indicates:
A
Higher inequality — the curve is bowing outward
B
Lower inequality — the distribution is more even
C
Perfect inequality — one person owns everything
D
That the Gini coefficient equals 1
Correct: B. The Lorenz curve bows below the diagonal. The closer it is to the diagonal, the more equal the distribution (small Area A → lower Gini). The further it bows away, the more unequal (large Area A → higher Gini). A country like Sweden has a Lorenz curve much closer to the diagonal than South Africa or the US.
Question 2 of 8 · Lorenz Curve & Gini Coefficient
Country X has a Gini of 0.25; Country Y has a Gini of 0.55. Which statement is correct?
A
Country X has higher inequality — a Gini closer to 0 means more inequality
B
Country Y has higher inequality — a Gini closer to 1 means more inequality
C
Both countries have the same inequality — Gini measures wealth, not income
D
Country Y has a more equal distribution of income
Answer · Question 2
Country X has a Gini of 0.25; Country Y has a Gini of 0.55. Which statement is correct?
A
Country X has higher inequality — a Gini closer to 0 means more inequality
B
Country Y has higher inequality — a Gini closer to 1 means more inequality
C
Both countries have the same inequality — Gini measures wealth, not income
D
Country Y has a more equal distribution of income
Correct: B. Gini coefficient: 0 = perfect equality; 1 = perfect inequality. Country Y's Gini of 0.55 indicates significantly more inequality than Country X's 0.25. For reference: Sweden ≈ 0.27 (low inequality); UK ≈ 0.36 (moderate); South Africa ≈ 0.63 (very high).
Question 3 of 8 · Lorenz Curve & Gini Coefficient
Why is wealth inequality typically much greater than income inequality in the UK?
A
Wealth is taxed more heavily than income, redistributing it more
B
Income data is more accurate than wealth data, understating income inequality
C
Wealth compounds over time via investment returns, and is concentrated further through inheritance
D
Wealth includes housing but income does not include rental income
Answer · Question 3
Why is wealth inequality typically much greater than income inequality in the UK?
A
Wealth is taxed more heavily than income, redistributing it more
B
Income data is more accurate than wealth data, understating income inequality
C
Wealth compounds over time via investment returns, and is concentrated further through inheritance
D
Wealth includes housing but income does not include rental income
Correct: C. Wealth accumulates: £100,000 invested at 5%/year becomes £432,000 in 30 years without adding to it. The wealthy reinvest returns, compounding advantage. Inheritance passes concentrated wealth to the next generation. By contrast, income differences are bounded by working life. UK wealth Gini (~0.62) is nearly double the income Gini (~0.36) for these reasons.
Question 4 of 8 · Lorenz Curve & Gini Coefficient
The Bank of England's QE programme (2009–2021) widened wealth inequality primarily because:
A
QE directly paid dividends to wealthy shareholders
B
QE reduced interest rates, making it cheaper for poor households to borrow
C
QE inflated financial asset prices (bonds, equities, property), most of which are owned by wealthier households
D
QE reduced government spending on welfare, harming low-income households
Answer · Question 4
The Bank of England's QE programme (2009–2021) widened wealth inequality primarily because:
A
QE directly paid dividends to wealthy shareholders
B
QE reduced interest rates, making it cheaper for poor households to borrow
C
QE inflated financial asset prices (bonds, equities, property), most of which are owned by wealthier households
D
QE reduced government spending on welfare, harming low-income households
Correct: C. QE works by buying financial assets, pushing up their prices and lowering yields. The wealthiest 10% own the vast majority of financial assets — so asset price inflation from QE translated into large wealth gains for them. The Bank of England's own 2012 analysis estimated the richest 10% gained ~£128,000 each in wealth from QE. Households with no savings or investments (typically lower-income) gained little.
Question 5 of 8 · Lorenz Curve & Gini Coefficient
The Oxfam 2023 report found the world's richest 1% captured nearly twice as much new wealth as the rest of humanity combined during 2020–22. Which factor most directly explains this?
A
Low-income workers received large government transfers during COVID
B
The pandemic boosted demand for low-skill work globally, raising wages at the bottom
C
Asset price inflation (driven by low interest rates and central bank stimulus) disproportionately benefited the wealthy
D
The richest 1% worked twice as many hours during the pandemic
Answer · Question 5
The Oxfam 2023 report found the world's richest 1% captured nearly twice as much new wealth as the rest of humanity combined during 2020–22. Which factor most directly explains this?
A
Low-income workers received large government transfers during COVID
B
The pandemic boosted demand for low-skill work globally, raising wages at the bottom
C
Asset price inflation (driven by low interest rates and central bank stimulus) disproportionately benefited the wealthy
D
The richest 1% worked twice as many hours during the pandemic
Correct: C. Central bank stimulus globally (QE, near-zero interest rates) inflated stock markets and property values. The world's richest individuals hold most of their wealth in these assets. Tech billionaires saw portfolios soar as digital services surged during COVID. This is the same mechanism as UK QE but at global scale — asset ownership is the primary driver of wealth divergence, not labour income.
Question 6 of 8 · Lorenz Curve & Gini Coefficient
Which of the following most effectively reduces income inequality at the BOTTOM of the distribution?
A
A higher top rate of income tax on earnings above £125,000
B
A wealth tax on financial assets above £500,000
C
An increase in the National Living Wage
D
Higher inheritance tax rates on estates above £1 million
Answer · Question 6
Which of the following most effectively reduces income inequality at the BOTTOM of the distribution?
A
A higher top rate of income tax on earnings above £125,000
B
A wealth tax on financial assets above £500,000
C
An increase in the National Living Wage
D
Higher inheritance tax rates on estates above £1 million
Correct: C. The NLW directly raises wages for the lowest-paid workers — the bottom of the income distribution. Empirically (Low Pay Commission data), the NLW has compressed wage inequality at the bottom without significant employment losses. The other options target the top of the distribution — they reduce top-end inequality but don't directly raise incomes at the bottom.
Question 7 of 8 · Lorenz Curve & Gini Coefficient
Richard Wilkinson and Kate Pickett (The Spirit Level) argued that higher inequality causes worse social outcomes. A strong critique of this argument is:
A
High-inequality countries always have higher GDP than low-inequality countries
B
The Spirit Level only measures income inequality, ignoring wealth
C
Correlation between inequality and bad outcomes doesn't prove causation — both may be driven by a third factor (e.g. trust, institutions)
D
Social outcomes are irrelevant to economic policy
Answer · Question 7
Richard Wilkinson and Kate Pickett (The Spirit Level) argued that higher inequality causes worse social outcomes. A strong critique of this argument is:
A
High-inequality countries always have higher GDP than low-inequality countries
B
The Spirit Level only measures income inequality, ignoring wealth
C
Correlation between inequality and bad outcomes doesn't prove causation — both may be driven by a third factor (e.g. trust, institutions)
D
Social outcomes are irrelevant to economic policy
Correct: C. Correlation ≠ causation. The Spirit Level shows that high-inequality countries have worse outcomes (health, crime, mobility). But critics argue both high inequality and bad outcomes may be caused by a common third factor — weak social institutions, low trust, historical factors. The cross-country regression approach cannot rule out confounding variables. This is a genuine empirical debate, not a settled fact.
Question 8 of 8 · Lorenz Curve & Gini Coefficient
A government increases benefits for low-income households funded by higher taxes on top earners. What is the most likely effect on the Gini coefficient?
A
Gini rises — taxes discourage work, reducing total income
B
Gini falls — redistribution compresses the income distribution
C
Gini is unchanged — redistribution moves income but doesn't change the total
D
Gini rises — benefits create a poverty trap reducing work incentives
Answer · Question 8
A government increases benefits for low-income households funded by higher taxes on top earners. What is the most likely effect on the Gini coefficient?
A
Gini rises — taxes discourage work, reducing total income
B
Gini falls — redistribution compresses the income distribution
C
Gini is unchanged — redistribution moves income but doesn't change the total
D
Gini rises — benefits create a poverty trap reducing work incentives
Correct: B. Progressive taxation + transfers directly compress the income distribution: top incomes fall post-tax; bottom incomes rise with benefits. UK: market income Gini ≈ 0.52 → post-tax-and-transfer Gini ≈ 0.36. The welfare state redistributes ~16 percentage points of Gini. This is the direct mechanical effect. Possible long-run offsetting effects (tax avoidance, reduced work incentives) are secondary and empirically contested.
🎓
Lesson Complete
You've covered the Lorenz curve, Gini coefficient, income vs wealth inequality, UK QE distributional effects, the Oxfam 2023 findings, consequences of inequality, and policy responses.