The Output Gap and the Self-Correcting Economy
Econlandia has a potential GDP of $800 billion and is currently producing $740 billion. The unemployment rate is 7.5%, while the natural rate is 5%. The marginal propensity to consume is 0.8, and the government collects a flat 25% of every additional dollar of income as tax. Prices and wages are sticky in the short run. The central bank has not changed the money supply, and the government's budget is currently balanced. Policymakers are debating whether to act or to let the economy adjust on its own.
1. Calculate the size of the output gap and identify whether Econlandia faces a recessionary or inflationary gap. Then determine the minimum change in government spending needed to close the gap, showing the multiplier arithmetic.
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Output gap = $800B − $740B = $60B recessionary gap (actual output is below potential).
Because taxes are proportional, the spending multiplier is not simply 1/(1−MPC). The marginal propensity to spend out of national income is MPC × (1 − t) = 0.8 × 0.75 = 0.6. So the multiplier = 1/(1 − 0.6) = 1/0.4 = 2.5.
Required ΔG = gap / multiplier = $60B / 2.5 = $24B.
So a $24B increase in government purchases closes the gap. Note: a tax cut would need to be larger because the tax multiplier is smaller than the spending multiplier (|−MPC/(1−MPC·(1−t))| = 0.8/0.4 = 2.0), so a tax cut would require $30B.
2. Suppose instead that no fiscal action is taken. Explain the self-correcting mechanism that returns Econlandia to potential GDP, and predict what happens to nominal wages, the price level, and real wages along the way.
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With output below potential, unemployment exceeds the natural rate, creating slack in labor markets. Nominal wages fall (or grow more slowly) as workers accept lower pay. Lower wages reduce firms' costs, shifting short-run aggregate supply rightward. As SRAS shifts right, the price level falls and real output rises until it returns to $800B potential.
Sequence: high unemployment → nominal wages ↓ → production costs ↓ → SRAS shifts right → price level ↓, real output ↑ toward potential. Real wages may fall in the short run but the adjustment restores full employment. This is the classical self-correction story; the key judgment is that the adjustment works through nominal wage flexibility, and if wages are sticky downward, the process is slow - which is the argument for activist policy.
3. A critic argues that if the government runs the $24B increase in spending financed by borrowing, crowding out could reduce the policy's effectiveness. Evaluate this claim and state the condition under which crowding out would be most severe.
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Crowding out occurs when deficit-financed spending raises interest rates and displaces private investment. If the government borrows $24B, demand for loanable funds rises, pushing up the real interest rate. Higher rates reduce interest-sensitive investment and consumption, partially offsetting the initial $60B boost.
Crowding out is most severe when the economy is near full employment (resources are already employed, so government use of them displaces private use), when investment is highly interest-elastic, and when the money supply is not accommodated. Here the economy is in a deep recessionary gap with slack, so crowding out is likely small - idle resources mean government borrowing competes less with private investment. The critic's claim is theoretically valid but empirically weak in this specific situation.