Economic Growth, Inflation (MV=PQ), Unemployment & The Phillips Curve

1

Measuring Economic Growth: Real vs Nominal GDP, GNI & PPP

Gross Domestic Product (GDP) is the total market value of all final goods and services produced within a country's geographical borders over a year; Gross National Income (GNI = GDP + Net Property Income from Abroad) adjusts for profits/remittances sent home by multinationals and migrant workers. Always distinguish three adjustments: 1. Nominal (Money) GDP vs real GDP: Nominal GDP is measured at current year prices (so if prices rise by 5% and physical output is unchanged, Nominal GDP rises by 5%!). Real GDP strips out inflation using a price deflator: Real GDP = (Nominal GDP ÷ Price Index) × 100. 2. Total vs per capita GDP: Dividing Real GDP by population size measures average output per person. 3. Purchasing power PARITY (PPP) Exchange Rates: Market exchange rates are distorted by speculative currency flows and ignore that non-traded services (haircuts, rent, street food) are much cheaper in developing countries. PPP adjusts GDP by comparing how much an identical basket of goods costs in different countries (e.g., The Economist's Big Mac Index).

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2

Limitations of GDP as a Measure of Living Standards & Easterlin Paradox

Why does higher Real GDP per capita not guarantee higher living standards or happiness? 1. Income Inequality: A surge in GDP captured entirely by the top 1% raises mean GDP per capita while leaving median household living standards stagnant. 2. The Shadow / Informal Economy: Unrecorded cash-in-hand work and subsistence farming mean official GDP understates true output (especially in developing nations). 3. Unpaid Work & Leisure Hours: GDP ignores unpaid domestic childcare, volunteering, and DIY - and if GDP rises only because workers work 70-hour weeks with zero leisure and high stress, welfare falls. 4. Negative Externalities & Composition of Output: GDP counts military spending and rebuilding after pollution/disasters as 'positives', while ignoring environmental depletion and CO₂ emissions. 5. The EASTERLIN PARADOX (Richard Easterlin 1974): Once a country's GDP per capita passes a threshold where basic needs are met (~$20,000, $30,000), further economic growth produces very little increase in self-reported life satisfaction because humans judge happiness by relative income comparison with peers and adapt quickly to higher consumption (the 'hedonic treadmill').

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3

Inflation, Deflation, Disinflation & How the CPI is Constructed

Inflation is a sustained increase in the general price level of goods and services over time (eroding the purchasing power of money). Disinflation is a fall in the rate of inflation (e.g., from 6% to 3% - prices are still rising, just more slowly). Deflation is a sustained decrease in the general price level (negative inflation, e.g., -1%). In the UK, the Office for National Statistics (ONS) calculates the Consumer Prices Index (CPI, target 2.0% ± 1%) every month using two surveys: 1. The Living Costs and Food Survey (~6,000 households) determines the proportion of average household budget spent on each item to assign weights (updated annually); 2. Around 180,000 price quotes across ~700 representative goods and services in the 'basket' are collected nationwide. Limitations of CPI: excludes owner-occupier housing costs like mortgage interest and council tax (which CPIH and RPI include), suffers from substitution bias (consumers switch to cheaper substitutes before annual weights update), fails to fully capture rapid quality improvements in smartphones/computers, and represents an 'average' household that matches nobody exactly.

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4

Causes of Inflation (Demand-Pull, Cost-Push, Fisher's MV = PQ) & Deflation

1. Demand-pull inflation: 'Too much money chasing too few goods' - when AD grows faster than LRAS (e.g., due to a consumer credit boom, fiscal stimulus, or export surge when near full capacity), shifting AD right from AD₁ to AD₂ and bidding up prices. 2. Cost-push inflation: When firms face rising production costs (e.g., imported oil/gas shock, sterling depreciation raising import prices, trade union wage rises exceeding productivity, or higher indirect taxes), shifting SRAS up/left from SRAS₁ to SRAS₂ and causing stagflation. 3. Quantity theory OF money (Irving Fisher 1911; Milton Friedman - 'Inflation is always and everywhere a monetary phenomenon'): Based on the Fisher Equation of Exchange: M × V ≡ P × Q (or PT), where M is the Money Supply, V is the Velocity of circulation of money, P is the general Price Level, and Q (or T) is Real Output/Transactions. Monetarists assume V is stable and Q is fixed at full-employment potential in the long run: therefore, any excessive expansion of the Money Supply (ΔM - such as excessive Quantitative Easing or central bank money-printing) causes a direct, proportional increase in the Price Level (ΔP)! 4. BENIGN vs MALIGN deflation: Benign (supply-side) deflation occurs when technological advances shift LRAS right (lowering unit costs while raising output); Malign (demand-side) deflation occurs in a slump when collapsing AD causes a deflationary spiral, consumers delay purchases expecting lower prices tomorrow, and the real burden of fixed nominal debts rises (Fisher debt-deflation, as in Japan's Lost Decades).

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5

Measuring Unemployment (ILO vs Claimant Count) & Types of Unemployment

1. Two Measures of Unemployment: ILO Labour Force Survey (LFS): Surveys ~40,000 households quarterly; counts anyone without a job who has actively sought work in the past 4 weeks and is available to start in the next 2 weeks (internationally comparable, captures those ineligible for benefits, but subject to sampling error). Claimant Count: Counts the exact number of people claiming unemployment-related benefits (Jobseeker's Allowance / Universal Credit; fast and free, but distorted whenever the government tightens benefit eligibility rules, and misses older/wealthier jobseekers). Note that ECONOMICALLY inactive people (students, early retirees, long-term sick, stay-at-home carers) are not counted as unemployed. 2. Types of Unemployment: Cyclical (Keynesian Demand-Deficient): Caused by a fall in AD during a recession (negative output gap). Structural: Caused by long-term decline of an industry (deindustrialisation/offshoring, regional, or technological automation) leaving workers occupationally and geographically immobile. Frictional (Search): Short-term transitional unemployment as workers move between jobs. SEASONAL: Fluctuations in tourism, agriculture, or construction. Classical (Real-Wage): Caused when powerful unions or an excessive minimum wage hold real wages above the market-clearing equilibrium W_e.

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6

The Short-Run (SRPC) and Long-Run (LRPC) Phillips Curves & NAIRU

1. Short-run PHILLIPS curve (A.W. Phillips 1958): Studying UK data from 1861-1957, Bill Phillips found an inverse (downward-sloping L-shaped) statistical trade-off between Unemployment (x-axis) and Wage/Price Inflation (y-axis). When government boosts AD, unemployment falls (say from 6% to 3%), creating labour shortages that allow workers to bid up wages, pushing inflation up (say from 2% to 5% - a movement up along the SRPC). 2. MILTON FRIEDMAN'S expectations-AUGMENTED long-run PHILLIPS curve (LRPC, 1968): Friedman predicted stagflation (which struck in the 1970s) by arguing there is NO trade-off between inflation and unemployment in the long run, the LRPC is vertical at the Natural Rate of Unemployment (NRU) or NAIRU (Non-Accelerating Inflation Rate of Unemployment, consisting of structural + frictional unemployment). Why? Starting at NAIRU (U* = 5%, inflation = 2% at Point A), if the government expands AD to cut unemployment to 3% (moving up SRPC₁ to Point B at 5% inflation), workers initially suffer from 'money illusion'; once workers realise prices have risen by 5%, they revise their inflation expectations upwards to 5% and demand 5% wage rises to restore real pay. Higher wage costs shift SRAS left and shift the Short-Run Phillips Curve upwards (from SRPC₁ to SRPC₂), returning unemployment right back to U* = 5% at Point C - now stuck with 5% inflation. Only Supply-Side Policies (training, housing mobility, welfare reform) can shift the vertical LRPC to the left.

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1. Q1

   In 2020 (the base year, Price Index = 100), Country X had a Nominal GDP of $500 billion and a population of 25 million. By 2025, Country X's Nominal GDP had risen to $660 billion, its Price Index (GDP deflator) had risen to 120, and its population had grown to 27.5 million. Calculate: (a) the percentage increase in Nominal GDP between 2020 and 2025, (b) Real GDP in 2025 at constant 2020 prices and the percentage increase in Real GDP, and (c) Real GDP per capita in 2020 and 2025, commenting on what happened to average living standards. (6 marks)

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   Click “Check Mark Scheme” to compare your answer, 1. (a) Percentage change in Nominal GDP = [(660 - 500) ÷ 500] × 100 = +32.0% [1 mark]. 2. (b) Real GDP in 2025 (at 2020 prices) = ($660 billion ÷ 120) × 100 = $550 billion [1 mark]. 3. Percentage increase in Real GDP = [(550 - 500) ÷ 500] × 100 = +10.0% [1 mark]. 4. (c) Real GDP per capita in 2020 = $500,000,000,000 ÷ 25,000,000 = $20,000 per person [1 mark]. 5. Real GDP per capita in 2025 = $550,000,000,000 ÷ 27,500,000 = $20,000 per person [1 mark]. 6. Comment: Although Nominal GDP rose by 32% and total Real GDP rose by 10%, because the population also grew by 10% (from 25m to 27.5m) while prices rose by 20%, Real GDP per capita remained completely unchanged at $20,000 - so average material output per person did not improve at all [1 mark].

2. Q2

   Explain how the Consumer Prices Index (CPI) is used to measure inflation in the UK, and evaluate the economic consequences of a high rate of inflation (e.g., 9% per year) on UK households, firms, and the macroeconomy. (8 marks)

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   Click “Check Mark Scheme” to compare your answer, 1. [AO1 Measuring CPI - 2 marks] The ONS measures CPI monthly by tracking ~180,000 price quotes for a representative basket of ~700 goods and services, multiplying each item's price change by a budget weight derived from the annual Living Costs and Food Survey of ~6,000 households. 2. [AO2 Consequences for Households & Redistribution - 2 marks] If CPI inflation (9%) exceeds nominal wage growth (say 5%), real wages fall by -4%, eroding living standards (especially for low-income households spending a high % on food and energy). Inflation also redistributes wealth unfairly: savers holding cash in bank accounts paying 3% interest suffer negative real interest rates (-6%), while borrowers (including the government) benefit as the real value of fixed nominal debt is eroded. 3. [AO2 Consequences for Firms & Trade - 2 marks] High inflation creates 'menu costs' (repricing catalogues/systems), 'shoe-leather costs' (searching for best prices/interest rates), and business uncertainty (freezing long-term capital investment I because future costs and revenues cannot be forecast), while if UK inflation (9%) exceeds trading partners' inflation (3%), UK exports become price-uncompetitive, worsening the Current Account (X - M). 4. [AO3 Evaluation - 2 marks] The severity of the impact depends on whether inflation is anticipated or unanticipated, whether it is driven by demand-pull (accompanied by booming jobs) or external cost-push stagflation (like 2022 imported gas prices), and how aggressively the Bank of England raises interest rates in response (which can trigger mortgage distress and recession).

3. Q3

   Using both Short-Run and Long-Run Phillips Curve diagrams reasoning, evaluate whether a government can permanently reduce unemployment by using expansionary fiscal and monetary policies. (8 marks)

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   Click “Check Mark Scheme” to compare your answer, 1. [AO1/AO2 Short-Run Trade-Off (Keynesian / A.W. Phillips 1958) - 2 marks] In the short run, expanding AD via tax cuts, infrastructure spending, or lower interest rates reduces cyclical (demand-deficient) unemployment: firms hire more workers to meet rising demand, moving the economy leftwards up along the Short-Run Phillips Curve (SRPC₁) from high unemployment (e.g., 7%) to low unemployment (e.g., 3%) at the cost of moderately higher demand-pull inflation. 2. [AO1/AO2 Long-Run Monetarist Critique (Friedman's Vertical LRPC at NAIRU) - 3 marks] However, Milton Friedman (1968) argued that once unemployment is pushed below the Natural Rate of Unemployment (NAIRU, where only structural and frictional unemployment exist), higher inflation erodes workers' real purchasing power. Once workers overcome 'money illusion', they revise their inflation expectations upwards and demand matching nominal wage rises. This increases firms' production costs (shifting SRAS left) and shifts the Short-Run Phillips Curve upwards (SRPC₁ to SRPC₂), returning unemployment back to the vertical LRPC at the NAIRU - leaving the economy with permanently higher inflation and zero permanent job gains. 3. [AO3 Evaluation: Hysteresis vs Supply-Side Policies - 3 marks] In conclusion, expansionary demand-side policy cannot reduce unemployment below the NAIRU permanently, only Supply-Side Policies (retraining, reducing geographical immobility, welfare reform) can shift the vertical LRPC leftwards. However, Keynesians counter that during a deep recession when actual unemployment is far above the NAIRU, expansionary AD policy IS essential to prevent 'hysteresis' (where long-term cyclical unemployment deskills workers and permanently raises the NAIRU itself).

4. Q4

   Compare the causes of structural unemployment and cyclical (demand-deficient) unemployment, and explain why they require completely different policy solutions. (5 marks)

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   Click “Check Mark Scheme” to compare your answer, 1. Causes: Cyclical unemployment is a macroeconomic problem affecting the whole economy during a recession when Aggregate Demand falls (AD₁ to AD₂), creating a negative output gap; in contrast, Structural unemployment is a microeconomic/sectoral supply-side problem caused by long-term shifts in comparative advantage (deindustrialisation/globalisation) or automation/AI, compounded by occupational and geographical immobility of labour [2 marks]. 2. Policy for Cyclical Unemployment: Because unemployed workers already possess skills that firms will need as soon as demand recovers, the appropriate remedy is Demand-Side stimulus, cutting interest rates (monetary policy) or increasing government infrastructure spending / cutting taxes (fiscal policy) to shift AD back to full employment [1.5 marks]. 3. Policy for Structural Unemployment: Boosting AD will not get a former coal miner or retail cashier a job as a software engineer (it will only cause bottleneck inflation); structural unemployment requires Interventionist and Market-Based Supply-Side Policies, adult retraining schemes, apprenticeships, regional enterprise zones, and affordable housing/transport links to improve occupational and geographical mobility [1.5 marks].

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