AP Macroeconomics exam technique: how to draw and label the Unit 1 and Unit 2 graphs and answer the free-response questions

What the AP Macroeconomics exam actually rewards

AP Macroeconomics is won and lost on two skills: drawing fully labelled graphs and reasoning in clear cause-and-effect chains. Because no calculator is allowed and the prose can be short, the free-response section is really a test of whether you can produce the right model, label it correctly, and explain what it shows. This guide pulls together the graphing and calculation technique for Units 1 and 2, each of which has its own dot-point page with practice questions: scarcity, opportunity cost and the PPC, comparative advantage, demand, supply, market equilibrium, the circular flow and GDP, and the rest of Unit 2.

The golden rule of AP graphs: label everything

Every AP graph earns its points from labels, not just shape. On any diagram you draw:

• Label both axes. For a market graph, the vertical axis is Price (or P) and the horizontal axis is Quantity (or Q). For the PPC, label each axis with one of the two goods.
• Name every curve. Demand is D, supply is S. When a curve shifts, show both positions and label them (D1 and D2, or S1 and S2).
• Mark the equilibrium. Show the original equilibrium price and quantity, and the new ones after any shift, with dashed lines to the axes if helpful.
• Show the direction of any shift with an arrow or clearly separated curves.

A correctly shaped but unlabelled graph typically earns zero. The grader is checking specific labels against a rubric, so labelling is not decoration, it is where the marks are.

The production possibilities curve

The PPC shows the maximum combinations of two goods with resources fully and efficiently used. To draw it:

1. Put one good on each axis and draw the curve. Use a bowed-outward curve for increasing opportunity cost (the usual case) or a straight line for constant opportunity cost.
2. A point on the curve is efficient; a point inside shows unemployment or inefficiency; a point outside is currently unattainable.
3. Growth (more resources or better technology) shifts the whole curve outward.

To find opportunity cost from a PPC table, take the amount of the good given up divided by the amount gained. From output data, the opportunity cost of one unit of a good is the quantity of the other good divided by the quantity of that good.

The supply and demand graph and shifts

The market graph is the workhorse of Unit 1. The make-or-break skill is distinguishing a movement along a curve from a shift of the curve:

For a single shift, redraw the curve, find the new intersection, and read off the new equilibrium. Remember the four single-shift outcomes: a demand increase raises both price and quantity; a demand decrease lowers both; a supply increase lowers price and raises quantity; a supply decrease raises price and lowers quantity.

For a double shift (both curves move), one of price and quantity is determinate and the other is indeterminate. Identify the variable both shifts push the same way (determinate) and the one they push opposite ways (indeterminate), and say so explicitly.

The standard Unit 2 calculations

Unit 2 is calculation-rich. Keep these formulas automatic, and always divide by the original value for any percentage change:

• Unemployment rate $= \dfrac{\text{unemployed}}{\text{labour force}} \times 100$, where labor force $=$ employed $+$ unemployed.
• Labor force participation rate $= \dfrac{\text{labour force}}{\text{working-age population}} \times 100$.
• Consumer Price Index $= \dfrac{\text{cost of basket in current year}}{\text{cost of basket in base year}} \times 100$.
• Inflation rate $= \dfrac{\text{CPI}_{\text{new}} - \text{CPI}_{\text{old}}}{\text{CPI}_{\text{old}}} \times 100$.
• Real GDP $= \dfrac{\text{nominal GDP}}{\text{GDP deflator}} \times 100$, and the GDP deflator $= \dfrac{\text{nominal GDP}}{\text{real GDP}} \times 100$.
• Real interest rate $\approx$ nominal interest rate $-$ inflation rate.

A useful shortcut: real GDP growth $\approx$ nominal GDP growth $-$ inflation, which works well for the small percentages the exam uses.

Matching your answer to the task verb

The free-response section uses specific AP task verbs, and each calls for a different kind of answer:

• Identify / State: a word or short phrase, no explanation needed.
• Calculate: show the formula, substitute, and give a labelled numerical answer (with units or a percent sign).
• Draw / Show / Use a graph: produce a fully labelled diagram that responds exactly to the prompt.
• Explain: give a cause-and-effect chain ("because X, then Y, so Z"), not just a restatement.

Answer each lettered part in order, keep prose tight, and let the graph carry any "show" task. Graders reward correct economics and clear reasoning over length, so a short, precise, fully labelled answer beats a long vague one.

A study sequence that works

Build the skills in this order so each rests on the last:

1. Definitions first. Lock down scarcity, opportunity cost, the factors of production, and the laws of demand and supply.
2. The two Unit 1 graphs. Draw the PPC and the supply-and-demand graph until labelling is automatic, then drill single and double shifts.
3. The Unit 2 calculations. Practice the unemployment rate, CPI and inflation, and real GDP conversions until you can do them without a calculator.
4. Cause-and-effect chains. Rehearse explaining each shift and each indicator in one or two precise sentences using the AP task verbs.
5. Timed free-response practice. Work released-style questions under time, then check your graphs and calculations against the scoring logic.

Check your technique

A mix of graphing, calculation, and reasoning questions covering Unit 1 and Unit 2 exam skills. Attempt them under timed conditions, then check against the solutions.

1. State the two things you must label on the axes of a supply and demand graph. (2 marks)
2. A good's own price falls. State whether this is a movement along or a shift of the demand curve. (1 mark)
3. From output data, a country can make 60 units of X or 30 units of Y. Calculate the opportunity cost of one unit of X. (2 marks)
4. A labor force of 150 million has 9 million unemployed. Calculate the unemployment rate. (2 marks)
5. The CPI rises from 250 to 275. Calculate the inflation rate. (2 marks)
6. Nominal GDP is $1,500 billion and the GDP deflator is 125. Calculate real GDP. (2 marks)
7. Both demand and supply increase (both shift right). State which of price and quantity is indeterminate. (2 marks)
8. A prompt says "Explain why the equilibrium price rises." State what kind of answer the verb Explain requires. (1 mark)