Fiscal Policy — AP Macroeconomics
1. Core Definitions and Policy Goals ★★☆☆☆ ⏱ 2 min
Fiscal policy is the use of government spending and taxation to influence aggregate demand, output, employment, and the price level in an economy. Unlike monetary policy set by an independent central bank, fiscal policy is set by a country's elected legislative and executive branches. It makes up 20-25% of Unit 3 exam weight, and appears regularly on both multiple-choice and free-response sections of the AP exam.
Fiscal policy is broadly categorized by its goal: **expansionary fiscal policy** closes recessionary output gaps, while **contractionary fiscal policy** closes inflationary output gaps. A key distinction is also made between discretionary fiscal policy (intentional new policy changes) and automatic stabilizers (pre-existing policies that adjust automatically over the business cycle).
2. Fiscal Policy Multipliers ★★★☆☆ ⏱ 4 min
Fiscal policy impacts on real GDP are amplified by the multiplier effect: every dollar of new spending becomes income for another household, which is then partially spent again, creating a chain of additional output. The size of the multiplier depends directly on the marginal propensity to consume ($MPC$), the share of additional income that households spend rather than save.
k_G = \frac{1}{1 - MPC} = \frac{1}{MPS}
k_T = -\frac{MPC}{1 - MPC} = -MPC \times k_G
To find the total change in real GDP ($\Delta Y$), multiply the change in policy by the corresponding multiplier: $\Delta Y = \Delta G \times k_G$ or $\Delta Y = \Delta T \times k_T$.
Exam tip: Always keep the negative sign on the tax multiplier. Forgetting the sign will lead you to recommend the wrong direction of policy, which is a common point deduction on FRQs.
3. Fiscal Policy in the AD-AS Model ★★★☆☆ ⏱ 4 min
Fiscal policy works by shifting the aggregate demand (AD) curve, since government spending ($G$) is a direct component of aggregate demand ($AD = C + I + G + NX$). Changes in taxes indirectly shift AD by changing household disposable income available for consumption.
When an economy is in recession, it has a **recessionary (negative) output gap**: short-run equilibrium real GDP is below potential GDP ($Y_p$), and unemployment is above the natural rate. To close this gap, policymakers use expansionary fiscal policy: increase government spending, cut taxes, or both. This shifts AD to the right, returning output to potential GDP.
When an economy produces above potential GDP, it has an **inflationary (positive) output gap**, and demand-pull inflation drives up the price level. Policymakers use contractionary fiscal policy: decrease government spending, raise taxes, or both. This shifts AD to the left, returning output to potential GDP and reducing inflationary pressure.
Exam tip: For FRQs that require an AD-AS diagram, always explicitly label the direction of your AD shift and the output gap. AP graders require clear labeling to earn full credit, even if your underlying logic is correct.
4. Discretionary Policy, Automatic Stabilizers, and Crowding Out ★★★★☆ ⏱ 4 min
- **Discretionary fiscal policy**: Intentional, new policy actions that require new legislation. Examples: passing a new infrastructure spending bill, enacting a one-time tax rebate. These have significant implementation lags.
- **Automatic stabilizers**: Pre-existing permanent policies that automatically adjust tax revenues and government spending over the business cycle, with no new legislation needed. Examples: progressive income taxes, unemployment benefits, which automatically boost AD during recessions.
The crowding-out effect is a key side effect of expansionary fiscal policy financed by government borrowing. When the government increases borrowing to fund higher spending, it increases demand for loanable funds, which raises the equilibrium real interest rate. Higher interest rates reduce private investment spending ($I$), shifting AD back to the left and partially offsetting the initial increase in output. Full crowding out occurs when the entire increase in government spending is offset by a decrease in private investment, leading to no net change in output.
Exam tip: On FRQs about crowding out, always explain the full mechanism: higher government borrowing increases real interest rates, which reduces private investment. You will lose points if you only state 'government spending replaces private spending' without the interest rate channel.
5. AP-Style Concept Check ★★★☆☆ ⏱ 6 min
Common Pitfalls
Why: Students confuse the tax multiplier with the government spending multiplier, since both depend on MPC.
Why: Students mix up policy direction and gap type.
Why: Students assume all tax policy is discretionary, ignoring that automatic stabilizers adjust without new legislation.
Why: Students mix up the direction of the offset effect.
Why: Students misread the question, which often asks for the policy change, not the change in output.