Macroeconomics

The big picture: how entire economies function, grow, and sometimes fail.

What Is Macroeconomics?

Macroeconomics studies the economy as a whole, not individual markets.

Micro FocusMacro Focus
One firm's pricingOverall price level (inflation)
One industry's outputTotal output (GDP)
Individual job searchEconomy-wide unemployment
One person's incomeNational income
One market's equilibriumEconomy-wide business cycles

Gross Domestic Product (GDP)

The most important measure of economic activity.

What GDP Measures

GDP = Total market value of all final goods and services produced within a country in a given period.

ComponentWhat It Includes% of US GDP
Consumption (C)Household spending on goods and services~68%
Investment (I)Business equipment, structures, inventories~18%
Government (G)Government purchases (not transfers)~17%
Net Exports (NX)Exports minus imports~-3%

GDP = C + I + G + (X - M)

GDP Calculation Example

ItemIncluded?Reason
New car purchaseYesFinal good
Steel sold to car makerNoIntermediate good (would double count)
Lawyer's feeYesService
Used furniture saleNoNot produced this period
Government salariesYesGovernment spending
Social Security checkNoTransfer payment
Homemade mealNoNot marketed
Drug dealNoUnderground economy

Real vs. Nominal GDP

TypeDefinitionUse
Nominal GDPMeasured in current pricesRaw dollar value
Real GDPAdjusted for inflationCompare across years
GDP DeflatorNominal/Real x 100Measure of price level

Example:

YearNominal GDPPrice IndexReal GDP
2020$21 trillion100$21 trillion
2025$28 trillion120$23.3 trillion

The economy really grew 11%, not 33%. The rest was inflation.

GDP Per Capita

GDP divided by population gives a rough measure of average living standards.

CountryGDP (2023)PopulationGDP Per Capita
USA$27 trillion335 million$80,000
China$18 trillion1.4 billion$13,000
Germany$4.4 trillion84 million$52,000
India$3.7 trillion1.4 billion$2,600

Limitations of GDP

What GDP MissesExample
DistributionHigh GDP can coexist with poverty
Unpaid workChildcare, housework, volunteering
Quality improvementsSmartphones replaced many devices
LeisureMore vacation time is valuable
Environmental costsPollution cleanup adds to GDP
Underground economyCash transactions, illegal activity
WellbeingMental health, social connections

GDP measures output, not welfare. It's a useful but incomplete metric.

Inflation

A sustained increase in the general price level.

Measuring Inflation

IndexWhat It MeasuresUse
CPI (Consumer Price Index)Basket of consumer goodsCost of living
Core CPICPI excluding food and energyUnderlying trend
PCEPersonal consumption expendituresFed's preferred measure
PPIProducer pricesEarly inflation signal
GDP DeflatorAll goods in GDPBroadest measure

CPI Basket Components

CategoryWeight (Approx.)
Housing33%
Transportation17%
Food14%
Medical care9%
Education/communication7%
Recreation6%
Apparel3%
Other11%

Types of Inflation

TypeCauseExample
Demand-pullToo much spendingEconomy overheating
Cost-pushRising production costsOil price shock
Built-inWage-price spiralWorkers expect inflation
MonetaryToo much money creationMoney supply grows faster than output
ImportedForeign prices riseWeak currency makes imports expensive

Why Inflation Matters

EffectExplanation
Erodes purchasing power$100 buys less over time
Redistributes wealthFrom savers to borrowers
Creates uncertaintyHard to plan and invest
Distorts signalsPrice changes from inflation vs. real factors
Shoe leather costsPeople minimize cash holdings
Menu costsBusinesses must update prices
Tax distortionsTaxed on nominal gains, not real

Inflation Rate Interpretation

RateInterpretationConcerns
0-1%Low inflationRisk of deflation
2%TargetOptimal for most central banks
3-4%ElevatedReduces purchasing power noticeably
5-10%HighEconomic distortions, social unrest
>10%Very highSerious economic problems
>50%/monthHyperinflationEconomic collapse

Unemployment

Types of Unemployment

TypeDefinitionExampleRemedy
FrictionalBetween jobs, searchingRecent graduate, job switcherJob search assistance
StructuralSkills don't match jobsCoal miner in service economyRetraining
CyclicalDue to recessionLayoffs during downturnStimulus
SeasonalRegular seasonal patternSki instructor in summerNone needed

Measuring Unemployment

TermDefinition
Labor forceEmployed + unemployed (actively seeking)
Unemployment rateUnemployed / Labor force x 100
Participation rateLabor force / Working-age population
U-6Broader measure including underemployed

Who Counts as Unemployed?

StatusCounted as Unemployed?
Lost job, actively searchingYes
Quit job, looking for new oneYes
Gave up lookingNo (discouraged worker)
Working part-time, wants full-timeNo (underemployed)
Full-time studentNo
RetiredNo
DisabledNo
Stay-at-home parentNo

Natural Rate of Unemployment

The unemployment rate when the economy is at full capacity.

ConceptDescription
Natural rateTypically 4-5% in developed economies
ComprisesFrictional + structural unemployment
ExcludesCyclical unemployment
Changes over timeDemographics, policies, technology

Below natural rate: Labor shortage, wage pressure, inflation rises Above natural rate: Economic slack, wage stagnation, inflation falls

Business Cycles

Phases of the Cycle

PhaseGDPUnemploymentInflationDuration
ExpansionRisingFallingRising3-10 years
PeakHighestLowestHighestMonths
RecessionFallingRisingFalling6-18 months
TroughLowestHighestLowestMonths
RecoveryRising againFallingStable1-2 years

What Causes Recessions?

TriggerExamples
Financial crisis2008-2009
Oil shock1973, 1979
Monetary tightening1981-1982
Pandemic2020
Asset bubble burst2001 (dot-com)
War/geopoliticalVarious

Recession Indicators

IndicatorWarning Sign
Yield curveInverted (short rates > long rates)
Unemployment claimsRising weekly claims
Consumer confidenceSharp decline
PMI (Purchasing Managers Index)Below 50
Housing startsDeclining
Leading Economic IndexMultiple months of decline

Aggregate Demand and Supply

Aggregate Demand (AD)

Total spending in the economy at each price level.

FactorEffect on AD
Consumer confidence upAD shifts right
Business investment upAD shifts right
Government spending upAD shifts right
Exports upAD shifts right
Tax cutsAD shifts right
Money supply upAD shifts right
Opposite of aboveAD shifts left

Aggregate Supply (AS)

Total output at each price level.

Short-Run ASLong-Run AS
Upward slopingVertical
Wages/prices stickyWages/prices flexible
Output can varyOutput at potential
Influenced by costsDetermined by resources and technology

Economic Shocks

Shock TypeExampleAD/AS EffectResult
Positive demandTax cut, stimulusAD rightHigher output, higher prices
Negative demandConsumer fearAD leftLower output, lower prices
Positive supplyTechnology advanceAS rightHigher output, lower prices
Negative supplyOil price spikeAS leftLower output, higher prices

Stagflation: Negative supply shock causes both high unemployment AND high inflation (worst of both worlds).

Economic Growth

Sources of Growth

FactorContribution
Labor force growthMore workers = more output
Human capitalEducation, skills, health
Physical capitalMachines, buildings, infrastructure
TechnologyMore output from same inputs
InstitutionsRule of law, property rights
TradeSpecialization and efficiency

Rule of 72

Years to double = 72 / growth rate

Growth RateYears to Double
1%72 years
2%36 years
3%24 years
5%14 years
7%10 years

Small differences matter: 1% vs 3% growth means the difference between 72 years and 24 years to double living standards.

Why Some Countries Are Rich

FactorRich CountriesPoor Countries
InstitutionsStrong property rights, rule of lawCorruption, weak enforcement
Human capitalHigh education levelsLow education
InfrastructureModern roads, internetPoor infrastructure
GeographyTemperate climate, coastal accessLandlocked, tropical disease
HistoryEarly industrializationColonial extraction
PoliciesMarket-friendlyProtectionist, unstable

Key Takeaways

  1. GDP measures economic output - Useful but imperfect measure of economic health; doesn't capture wellbeing

  2. Inflation erodes purchasing power - Central banks target 2% as optimal balance between costs and benefits

  3. Unemployment has multiple types - Cyclical responds to policy; structural and frictional are always present

  4. Business cycles are normal - Recessions are painful but regular; average expansion lasts longer than contraction

  5. Aggregate demand and supply - Framework for understanding how shocks affect the entire economy

  6. Growth compounds dramatically - Small differences in growth rates create huge differences over decades

  7. Institutions matter most for development - Property rights, rule of law, and stability enable prosperity