UNIT 2 · SLIDE 1
The Circular Flow Model
PRODUCT MARKET
households BUY goods & services · firms SELL
Households
own the factors
Firms
produce output
FACTOR MARKET
firms BUY labor & resources · households EARN wages
Two loops, one economy
Money flows one direction; goods, services, and
resources flow the other. Every dollar spent is earned.
Leakages vs. injections
Leakages OUT: savings, taxes, imports
Injections IN: investment, gov spending, exports
Why it matters for GDP
Total spending = total income = total output, so GDP
can be measured by expenditure OR income approach.
One person's spending is another person's income — that identity powers the whole model.
The Review Hub · AP Macroeconomics Unit 2
Households sell resources and buy products; firms buy resources and sell products. Money circulates one way, real stuff the other — which is why total spending, income, and output are all the same number: GDP .
UNIT 2 · SLIDE 2
GDP and Its Four Components
GDP = C + I + G + Xn
C · Consumption
Household spending —
the biggest slice (~68%
of U.S. GDP).
I · Investment
Business equipment, new
construction, inventories.
NOT stocks or bonds!
G · Government
Purchases of goods &
services only. Transfer
payments don't count.
Xn · Net exports
Exports − imports.
Imports SUBTRACT —
Xn is usually negative.
What GDP does NOT count
• Intermediate goods (avoids double counting)
• Used / secondhand sales (already counted once)
• Financial transactions — stocks & bonds
• Transfer payments (Social Security, welfare)
• Nonmarket production (your own housework)
• Underground / illegal economy
MCQ trap: buying a share of stock is NOT investment —
only new capital goods count as "I".
GDP = market value of all FINAL goods & services produced within a country in a year.
The Review Hub · AP Macroeconomics Unit 2
Memorize C + I + G + Xn and the exclusion list. The most-tested traps: transfer payments aren't in G, buying stock isn't investment, and imports subtract from GDP.
UNIT 2 · SLIDE 3
Unemployment — Measurement & Types
The formulas
Unemployment rate = unemployed ÷ labor force × 100
Labor force = employed + unemployed (16+, seeking)
LFPR = labor force ÷ adult population × 100
Why the official rate misleads
• Discouraged workers stopped searching — they're
NOT in the labor force, so the rate UNDERSTATES
• Part-time workers who want full-time still count
as fully employed (underemployment hidden)
Retirees, students, stay-at-home parents: not in labor force
Frictional — between jobs
Job search, new grads. Short-term, always exists,
even healthy — better matches take time.
Structural — skills mismatch
Technology or trade makes skills obsolete
(automation). Longer-lasting; needs retraining.
Cyclical — recession-driven
Caused by downturns in the business cycle.
Equals ZERO at full employment.
Natural rate of unemployment = frictional + structural (≈ 4–5%) — full employment ≠ 0%.
The Review Hub · AP Macroeconomics Unit 2
Know the formula, the three types, and the traps: discouraged workers make the rate understate joblessness, and "full employment" still includes frictional + structural unemployment — the natural rate .
UNIT 2 · SLIDE 4
Measuring the Price Level: Real GDP, Deflator & CPI
Real vs. nominal GDP
Nominal = valued at CURRENT prices
Real = valued at BASE-YEAR prices (inflation removed)
Always compare years using REAL GDP
In the base year, real GDP = nominal GDP
GDP deflator
Deflator = (nominal GDP ÷ real GDP) × 100
Real GDP = nominal ÷ (deflator ÷ 100)
Rearrange the deflator formula for any missing piece.
CPI — the consumer price index
CPI = (basket cost now ÷ basket cost in base yr) × 100
Inflation rate = % change in CPI between years
Tracks a FIXED basket a typical consumer buys
Inflation = (CPI new − CPI old) ÷ CPI old × 100
Why CPI overstates inflation
• Substitution bias — buyers switch to cheaper goods
• New products enter the basket late
• Quality improvements look like pure price hikes
Deflator covers ALL domestic output; CPI only consumer goods.
Real values strip out inflation — only real GDP growth means the economy actually produced more.
The Review Hub · AP Macroeconomics Unit 2
Nominal uses current prices; real uses base-year prices. The GDP deflator converts between them, and CPI tracks a fixed consumer basket — know both formulas and CPI's upward biases.
UNIT 2 · SLIDE 5
Two Kinds of Inflation — and Who It Hurts
Demand-pull inflation
"Too much money chasing too few goods"
• AD shifts RIGHT (spending boom, stimulus)
• Price level ↑ AND real output ↑
Typical late in an expansion, beyond full employment
Cost-push inflation
Supply-side shock raises production costs
• SRAS shifts LEFT (oil shock, wage spike)
• Price level ↑ BUT real output ↓
= STAGFLATION — the worst of both worlds
UNEXPECTED inflation helps…
• Borrowers — repay with cheaper dollars
• Anyone locked into paying fixed rates
The real value of the debt they owe shrinks
…and hurts
• Lenders & savers — repaid in weaker dollars
• People on fixed incomes (pensions)
Plus menu costs & shoe-leather costs for everyone
Unexpected inflation redistributes wealth from lenders to borrowers — anticipated inflation gets priced in.
The Review Hub · AP Macroeconomics Unit 2
Demand-pull: AD right, output and prices both rise. Cost-push: SRAS left, prices rise while output falls (stagflation ). Unexpected inflation transfers wealth from lenders and savers to borrowers.
UNIT 2 · SLIDE 6
The Business Cycle
peak
trough
recession ↓
expansion ↑
trend growth
Real GDP
Time
The four phases
Expansion → Peak → Recession → Trough → repeat
Recession ≈ two consecutive quarters of falling
real GDP; unemployment rises, inflation cools.
Output gaps (preview of Unit 3)
Below trend = recessionary gap (cyclical unemployment)
Above trend = inflationary gap (overheating)
The dashed line = potential output (full employment)
— it grows over time as LRAS / the PPC shifts out.
The economy fluctuates AROUND its long-run trend — gaps between actual and potential drive all of Unit 3.
The Review Hub · AP Macroeconomics Unit 2
Real GDP cycles around a rising trend: expansion, peak, recession, trough . Where actual output sits relative to potential output defines the gaps that Unit 3's AD/AS model analyzes.
UNIT 2 · SLIDE 7
What GDP Can't Tell You
Missing production
Household work, volunteering, and the underground
economy never show up in official GDP.
Says nothing about distribution
A rising total can hide stagnant incomes for most
people — GDP is a total, not a distribution.
Ignores costs of growth
Pollution and environmental damage aren't
subtracted; cleanup spending even ADDS to GDP.
Ignores leisure & well-being
Working every waking hour would raise GDP —
but not quality of life. Leisure has value too.
The better yardstick for living standards
Real GDP per capita = real GDP ÷ population
Adjusts for both inflation AND population — the standard measure for comparing countries or eras
GDP measures production, not happiness — use real GDP per capita when comparing living standards.
The Review Hub · AP Macroeconomics Unit 2
GDP misses nonmarket and underground production, ignores distribution, environmental costs, and leisure. For living standards, the exam wants real GDP per capita .
UNIT 2 · SLIDE 8
Unit 2 Quick Reference — Know These Cold
Core formulas
Unemployment = unemployed ÷ labor force × 100
Inflation = %Δ CPI · Deflator = nominal ÷ real × 100
GDP = C + I + G + Xn
Real GDP per capita = the living-standards measure
GDP counting rules
Final goods only · produced THIS year · within borders
No transfers, used goods, or financial assets
Imports subtract; inventory changes count in I
Spending approach = income approach = output
Unemployment types
Frictional (searching) + Structural (mismatch)
= natural rate · Cyclical = recession only
Discouraged workers → rate understates
Full employment = natural rate, NOT zero
Inflation essentials
Demand-pull: AD→, P↑ Y↑ · Cost-push: SRAS←, P↑ Y↓
Unexpected inflation: borrowers win, lenders lose
CPI overstates (substitution, quality, new goods)
Anticipated inflation gets built into nominal rates
Unit 2 is 12–17% of the exam — indicator definitions and calculation questions are easy points to lock in.
The Review Hub · AP Macroeconomics Unit 2
Everything Unit 2 tests: the formulas, the GDP counting rules, the three unemployment types, and the two inflation stories. These are the fastest points on the whole exam.