Long-Run Adjustment
When situations happen in the short-run that shift either aggregate demand or aggregate supply, there has to be an adjustment back to the long-run. In the absence of government intervention, the economy self corrects itself in a variety of different ways. In a sense, long term adjustment is basically price adjustment. It's about bringing things back to long-run equilibrium. In AP Macroeconomics, long-run equilibrium means real GDP returns to full-employment output and unemployment returns to the natural rate as wages and prices become flexible.
Shocks
Macroeconomic shocks can shift either aggregate demand (AD) or short-run aggregate supply (SRAS). In the short run, these shocks can change real output, employment, unemployment, and the price level. In the long run, if the shock is temporary and there is no government intervention, flexible wages and prices move the economy back to full-employment output.
Required Long-Run Outcomes After AD and SRAS Shocks
If AD decreases, real GDP falls below full-employment output in the short run, unemployment rises above the natural rate, and the price level falls. Over time, nominal wages and other input prices fall, SRAS shifts right, real GDP returns to full-employment output, unemployment returns to the natural rate, and the price level settles at a lower level than before. If AD increases, real GDP rises above full-employment output in the short run, unemployment falls below the natural rate, and the price level rises. Over time, nominal wages and other input prices rise, SRAS shifts left, real GDP returns to full-employment output, unemployment returns to the natural rate, and the price level settles at a higher level than before. If SRAS decreases, real GDP falls and the price level rises in the short run; over time, as wages and input prices adjust downward, SRAS shifts right and the economy returns to full-employment output and the natural rate of unemployment. If SRAS increases, real GDP rises and the price level falls in the short run; over time, as wages and input prices adjust upward, SRAS shifts left and the economy returns to full-employment output and the natural rate of unemployment.
Graphically, the economy begins at the intersection of AD, SRAS, and LRAS. After a negative AD shock, AD shifts left, creating a recessionary gap where output is below LRAS. Over time, lower nominal wages shift SRAS right until it intersects AD at LRAS. After a positive AD shock, AD shifts right, creating an inflationary gap where output is above LRAS. Over time, higher nominal wages shift SRAS left until it intersects AD at LRAS. After a negative SRAS shock, SRAS shifts left, causing stagflation in the short run; if the shock is temporary, falling wages/input prices later shift SRAS right back to LRAS output. After a positive SRAS shock, SRAS shifts right; if the shock is temporary, rising wages/input prices later shift SRAS left back to LRAS output.
These self-correcting mechanisms enable the economy to return to long-run equilibrium without government intervention.
Let's look at all the various ways the economy can self correct itself back to the long-run. These are all situations where you begin in long-run equilibrium, a change occurs to move you to short-run and the economy has to self-correct back to long-run equilibrium.
Recessionary Gap
You'll remember from earlier that during a recessionary gap, the equilibrium (B) is on the left side of LRAS. SRAS1 and AD are intersecting at B instead of It describes a situation where the economy is producing within its production possibilities frontier. The gap between Q2 and Yf describes the shortfall of real GDP and from full employment. As you can see, LRAS does not intersect at B, but in order to have a long-term equilibrium, we need LRAS to intersect as well.
This is because recession causes the economy to not take advantage of all of its resources like labor. Because unemployment is above the natural rate during a recessionary gap, nominal wages and other input prices tend to fall over time. Lower production costs increase short-run aggregate supply, so SRAS shifts right and the economy moves back to full-employment output. Since the worker's wages are decreasing, there is a decrease in production costs for firms. This will cause the economy to self-correct by moving from SRAS1 back to SRAS.
Inflationary Gap
Inflation happens when the economy is over-producing. The equilibrium (B) is on the right side of LRAS and real GDP is above the full-employment potential. But because LRAS doesn't intersect SRAS and AD, we have a problem. High production can strain resources and labor is working overtime. This will cause workers to ask for an increase in wages and cause supply to go down. This will then cause a decrease in aggregate supply (SRAS1 to SRAS) bringing the economy back to long-run equilibrium.
This is how the economy self-corrects after an inflationary gap, when output is above full-employment output and unemployment is below the natural rate in the short run. After the long-run adjustment, the price level is higher than it was at the start of the inflationary gap. In AP Macroeconomics, the key point is that self-adjustment restores real GDP to full-employment output, but the final price level may be higher after a positive AD shock or lower after a negative AD shock.
Permanent Shocks and LRAS
If the shock is permanent and makes the entire economy less productive, the entire capacity of the economy will decrease. In this case, LRAS will shift to the left (think of this as a shrinking of the production possibilities frontier). Because production costs are now higher, SRAS will also decrease and output will be permanently lower, leading to a permanently higher price level.
LRAS Shifts and Economic Growth
Unlike self-adjustment after AD or SRAS shocks, a shift in LRAS changes the economy's full-employment level of real GDP itself. A rightward shift of LRAS means the economy's productive capacity has increased, so potential output and full-employment output are higher than before. This represents long-run economic growth. A leftward shift of LRAS means the economy's productive capacity has decreased, so potential output and full-employment output are lower than before. On an AD-AS graph, LRAS shifts show changes in where the economy can produce at full employment in the long run. Self-adjustment after an AD or SRAS shock returns the economy to LRAS; an LRAS shift changes the location of that long-run equilibrium output.
In the long run, self-adjustment after AD or SRAS shocks occurs because wages and input prices are flexible. When output is below full-employment output, wages and input prices tend to fall, shifting SRAS right. When output is above full-employment output, wages and input prices tend to rise, shifting SRAS left. This process returns real GDP to full-employment output and unemployment to the natural rate. By contrast, changes in resources, technology, or productivity shift LRAS and change the economy's full-employment level of output. In the long run, increases in LRAS raise the economy's full-employment output, while self-adjustment after AD or SRAS shocks returns the economy to whatever full-employment output currently exists.
For this topic, focus on how the economy self-adjusts in the absence of government intervention.
Vocabulary
The following words are mentioned explicitly in the College Board Course and Exam Description for this topic.
| Term | Definition |
|---|---|
| aggregate demand | The total quantity of goods and services demanded across an entire economy at different price levels. |
| aggregate output | The total quantity of goods and services produced in an economy, typically measured as real GDP. |
| aggregate supply shock | An unexpected event that causes a sudden shift in the aggregate supply curve, affecting the economy's ability to produce goods and services. |
| economic growth | An increase in the production of goods and services in an economy over time, measured by the growth rate of real GDP per capita. |
| employment | The state of having a paid job or being engaged in work for compensation. |
| flexible wages and prices | The ability of wages and prices to adjust upward or downward in response to changes in supply and demand. |
| full employment | An economic condition where all available labor resources are being used efficiently and unemployment is at its natural rate. |
| long run | A time period in macroeconomics where all factors of production are variable and prices fully adjust to changes in supply and demand. |
| Long-Run Aggregate Supply curve | A vertical line on a graph representing the maximum sustainable output an economy can produce when all resources are fully employed and wages and prices have fully adjusted. |
| natural rate of unemployment | The unemployment rate that exists when the economy produces full-employment real output, equal to the sum of frictional and structural unemployment. |
| price level | The average of all prices of goods and services produced in an economy, typically measured by price indices like the CPI. |
| short-run aggregate supply | The total quantity of goods and services that firms are willing to produce at different price levels in the short run, when some prices are sticky. |
Frequently Asked Questions
What is long-run self-adjustment and how does it work in the economy?
Long-run self-adjustment is the economy’s automatic way of returning output and employment to full-employment (potential) output after an AD or SRAS shock, without government policy. In the short run sticky wages/prices make output deviate from YF and unemployment move away from the natural rate. Over time wages, input prices, and inflation expectations become flexible: if AD falls (recessionary gap), wages eventually fall, SRAS shifts right, and real GDP returns to LRAS while unemployment returns to the natural rate; if AD rises (inflationary gap), rising wages shift SRAS left and price level rises back while output returns to YF. Remember: shifts in LRAS mean a change in full-employment output (economic growth). On the AP exam you should draw AD, SRAS, LRAS and explain how SRAS shifts restore long-run equilibrium (see the Topic 3.7 study guide for a quick refresher: https://library.fiveable.me/ap-macroeconomics/unit-3/long-run-self-adjustment/study-guide/VeYA6gFFsLYxu92do3Od). For unit review: https://library.fiveable.me/ap-macroeconomics/unit-3 and practice problems: https://library.fiveable.me/practice/ap-macroeconomics.
How do wages and prices adjust automatically to bring the economy back to full employment?
If output is off full employment, wages and prices adjust so unemployment returns to the natural rate. Example: a negative AD shock lowers real GDP below potential (recessionary gap). With unemployment above the natural rate, nominal wages fall over time as workers accept lower pay and firms face less pressure to raise prices. Lower wages reduce firms’ costs, shifting SRAS rightward until output returns to LRAS (full-employment output) at a lower price level. The reverse happens with an inflationary gap: high demand raises wages and input costs, SRAS shifts left until unemployment returns to its natural rate and price level is higher. On the AP exam you should draw AD, SRAS, and vertical LRAS and explain how wage/price flexibility and inflation expectations cause the self-correction (CED EK MOD-2.I.1). For a focused review check the Topic 3.7 study guide (https://library.fiveable.me/ap-macroeconomics/unit-3/long-run-self-adjustment/study-guide/VeYA6gFFsLYxu92do3Od), unit overview (https://library.fiveable.me/ap-macroeconomics/unit-3), and practice questions (https://library.fiveable.me/practice/ap-macroeconomics).
I'm confused about why the economy returns to the natural rate of unemployment on its own - can someone explain?
Think of the long-run self-adjustment as the economy fixing an output gap without policy because wages and prices are flexible (CED EK MOD-2.I.1). If AD falls and output drops below full-employment, unemployment rises above the natural rate. Firms see lower demand and cut hours/wages slowly, but workers and firms expect lower inflation, so nominal wages eventually fall. Lower wages reduce production costs, SRAS shifts right, and output moves back to potential (YF) while the price level falls. The reverse happens after an inflationary AD shock: higher inflation raises nominal wages and SRAS shifts left until unemployment returns to the natural rate. This is the self-correction mechanism and why the long-run Phillips curve is vertical at the natural unemployment rate. On the exam you’ll usually show this with an AD–SRAS–LRAS graph (free-response requires drawing/labeling). For a quick review, see the Topic 3.7 study guide (https://library.fiveable.me/ap-macroeconomics/unit-3/long-run-self-adjustment/study-guide/VeYA6gFFsLYxu92do3Od), Unit 3 overview (https://library.fiveable.me/ap-macroeconomics/unit-3), or practice questions (https://library.fiveable.me/practice/ap-macroeconomics).
What's the difference between short-run and long-run aggregate supply curves?
Short-run aggregate supply (SRAS) is upward sloping because some wages and input prices are sticky: when the price level rises firms get higher profits and increase output, so real GDP can deviate from full-employment output. Long-run aggregate supply (LRAS) is vertical at potential (full-employment) output—in the long run wages and prices are flexible so the economy self-corrects back to the natural rate of unemployment and potential GDP regardless of the price level (CED EK MOD-2.I.1, EK MOD-2.I.2). Practically: a demand shock shifts AD and moves you along SRAS (changing output and the price level). Over time wages/expectations adjust, SRAS shifts and the economy returns to LRAS (self-correction). Supply shocks shift SRAS; permanent changes in resources/technology shift LRAS. On the AP exam you’ll often draw AD/SRAS/LRAS to show short-run impacts and the long-run adjustment (practice this for FRQs). For a quick review, see the Topic 3.7 study guide (https://library.fiveable.me/ap-macroeconomics/unit-3/long-run-self-adjustment/study-guide/VeYA6gFFsLYxu92do3Od) and more unit review (https://library.fiveable.me/ap-macroeconomics/unit-3). For extra practice, try the AP Macro problem set (https://library.fiveable.me/practice/ap-macroeconomics).
How do I draw a graph showing the economy self-adjusting after a negative demand shock?
Draw AD-AS with price level on vertical axis and real GDP (output) on horizontal. Start with AD0, SRAS0, and vertical LRAS at full-employment output YF. Show a negative demand shock by shifting AD left to AD1. Label the short-run equilibrium at the intersection of AD1 and SRAS0 as Y1 (Y1 < YF) and PL1—this is a recessionary gap (output below potential, cyclical unemployment up). For long-run self-adjustment, note flexible wages/prices fall → firms’ costs drop → SRAS shifts right (SRAS1) until it intersects AD1 at LRAS (YF). Label new short-run aggregate supply and the new price level PL2 (PL2 < PL1). Output returns to YF, unemployment returns to the natural rate; only the price level changed. On the AP exam you must draw and label AD, SRAS, LRAS, show Y1, PL1, and YF and explain the wage-price adjustment (CED EK MOD-2.I). For a study guide and extra practice see the Topic 3.7 guide (https://library.fiveable.me/ap-macroeconomics/unit-3/long-run-self-adjustment/study-guide/VeYA6gFFsLYxu92do3Od), Unit 3 overview (https://library.fiveable.me/ap-macroeconomics/unit-3), and practice questions (https://library.fiveable.me/practice/ap-macroeconomics).
When aggregate demand shifts left, why does the economy eventually return to the same output level?
When AD shifts left, short-run real GDP falls below full-employment output (a recessionary gap) and the price level falls. Because wages and many input prices are flexible in the long run, lower prices reduce firms’ nominal costs and workers’ wage demands eventually adjust down. As nominal wages and other input costs fall, the short-run aggregate supply (SRAS) curve shifts rightward until it intersects AD at the vertical long-run aggregate supply (LRAS)—the economy’s potential output. Thus real GDP returns to the same full-employment level and unemployment returns to the natural rate; the adjustment shows up as a lower price level (not permanently lower output). This is the AD-AS self-correction mechanism emphasized in the CED (EK MOD-2.I.1). On the AP exam you should show this with an AD left shift on an AD–SRAS–LRAS graph and explain wage/price flexibility (see the Topic 3.7 study guide for a quick review) (https://library.fiveable.me/ap-macroeconomics/unit-3/long-run-self-adjustment/study-guide/VeYA6gFFsLYxu92do3Od). For more practice, try problems at (https://library.fiveable.me/practice/ap-macroeconomics).
What happens to employment and price level during long-run self-adjustment?
In the long run, flexible wages and prices restore full employment: after a shock to AD or SRAS, real GDP returns to potential (full-employment) output and the unemployment rate goes back to the natural rate. What changes permanently is the price level—it rises after a positive AD shock and falls after a negative AD shock (and if SRAS shifts in the short run, long-run wage/price adjustments move SRAS back so output returns to YF while PL adjusts). So employment returns to its natural level; the long-run effect is on the price level, not on real output or long-run employment. You should be ready to draw AD, SRAS, and a vertical LRAS and explain this on the free-response (Topic 3.7, EK MOD-2.I.1). For a quick review, see the Topic 3.7 study guide (https://library.fiveable.me/ap-macroeconomics/unit-3/long-run-self-adjustment/study-guide/VeYA6gFFsLYxu92do3Od) and more unit practice (https://library.fiveable.me/ap-macroeconomics/unit-3); practice questions are at (https://library.fiveable.me/practice/ap-macroeconomics).
I don't understand how flexible wages help the economy recover from recessions without government help.
Flexible wages mean workers’ pay can fall when demand for labor drops. In a recession AD falls, output and employment drop below potential (a recessionary gap). With no policy, wages slowly fall (or wage growth slows). Lower nominal wages reduce firms’ costs, so the short-run aggregate supply (SRAS) curve shifts right. As SRAS shifts right, real GDP rises back to full-employment output and unemployment returns to the natural rate while the price level falls or stabilizes. That’s the self-correction mechanism AP wants you to explain (use an AD–SRAS–LRAS graph on FRQs). For a clear step-by-step graphic and wording the CED expects, check the Topic 3.7 study guide (https://library.fiveable.me/ap-macroeconomics/unit-3/long-run-self-adjustment/study-guide/VeYA6gFFsLYxu92do3Od). If you want practice drawing and explaining these shifts, try problems at Fiveable’s Unit 3 page (https://library.fiveable.me/ap-macroeconomics/unit-3) or the practice question bank (https://library.fiveable.me/practice/ap-macroeconomics).
How do supply shocks affect the economy differently in the short run vs long run?
Short-run: a negative supply shock (like higher oil prices) shifts SRAS left → price level rises and real GDP falls (stagflation). Firms cut output, unemployment rises above the natural rate. Because wages and some prices are sticky, the economy doesn’t immediately return to full-employment output. Long-run: with no policy action, flexible wages and prices adjust (wages fall or inflation expectations change), SRAS gradually shifts back (or nominal wages rise after a positive shock), restoring output to potential (LRAS), and unemployment returns to the natural rate. The lasting effect of a pure supply shock is on the price level (higher or lower), not long-run output, unless LRAS itself shifts (e.g., productivity change). On the AP, you should show this with AD, SRAS and vertical LRAS on an AD-AS graph and explain wage-price flexibility and the self-correction mechanism (see the Topic 3.7 study guide: https://library.fiveable.me/ap-macroeconomics/unit-3/long-run-self-adjustment/study-guide/VeYA6gFFsLYxu92do3Od). For more unit review and practice problems, check (https://library.fiveable.me/ap-macroeconomics/unit-3) and (https://library.fiveable.me/practice/ap-macroeconomics).
What causes the long-run aggregate supply curve to shift and what does that mean for economic growth?
The LRAS curve shifts when the economy’s productive capacity changes—i.e., when potential (full-employment) output changes. Factors that shift LRAS: more/better resources (labor force growth, higher labor quality), increases in physical or human capital, technological progress, and institutional improvements (better property rights, infrastructure). A rightward shift means higher potential GDP and long-run economic growth; a leftward shift means a drop in potential output. On the AP exam you should show this with a vertical LRAS moving right or left and explain implications for output, unemployment (returns to the natural rate), and the price level after AD/SRAS shocks (see EK MOD-2.I.1 and EK MOD-2.I.2). For targeted review, check the Topic 3.7 study guide (https://library.fiveable.me/ap-macroeconomics/unit-3/long-run-self-adjustment/study-guide/VeYA6gFFsLYxu92do3Od) and Unit 3 overview (https://library.fiveable.me/ap-macroeconomics/unit-3). For extra practice, use Fiveable’s practice problems (https://library.fiveable.me/practice/ap-macroeconomics).
Can you explain why unemployment goes back to its natural rate even after major economic shocks?
After a demand or short-run supply shock, output and unemployment move away from their full-employment (natural) levels in the short run because wages and some prices are sticky. In the long run, wages and inflation expectations are flexible: if output is above potential, firms bid up wages and input prices, which shifts SRAS left; if output is below potential, wages fall, shifting SRAS right. Those SRAS shifts continue until real GDP equals potential (LRAS, vertical)—at that point the unemployment rate returns to the natural rate. In other words, price-wage flexibility and changing inflation expectations provide a self-correction mechanism that restores long-run equilibrium (no government action needed). For AP exam tasks you should be able to draw AD, SRAS, and LRAS showing SRAS shifting back to intersect AD at LRAS (Topic 3.7). Review the topic study guide (https://library.fiveable.me/ap-macroeconomics/unit-3/long-run-self-adjustment/study-guide/VeYA6gFFsLYxu92do3Od) and practice AD-AS graphs (https://library.fiveable.me/ap-macroeconomics/unit-3) or try practice problems (https://library.fiveable.me/practice/ap-macroeconomics).
How long does it actually take for wages and prices to adjust in real life?
Short answer: there’s no fixed clock—adjustment can take months to several years. The CED’s long-run self-adjustment idea says flexible wages and prices will eventually move output back to potential and unemployment to the natural rate, but “eventually” depends on how sticky wages/prices and inflation expectations are. For typical demand shocks economists often point to roughly 1–3 years for wages/expectations to catch up; big supply shocks (oil, large policy shifts) can take longer. Key drivers: length of wage contracts, degree of price stickiness, how fast inflation expectations update, and labor-market frictions. On the AP exam you should explain this concept with an AD–SRAS–LRAS graph and mention wage/price flexibility and expectation changes (Topic 3.7). For a quick review, see the Topic 3.7 study guide (https://library.fiveable.me/ap-macroeconomics/unit-3/long-run-self-adjustment/study-guide/VeYA6gFFsLYxu92do3Od), unit overview (https://library.fiveable.me/ap-macroeconomics/unit-3), and practice questions (https://library.fiveable.me/practice/ap-macroeconomics) to practice explaining time paths on graphs.
What's the difference between a movement along LRAS and a shift of the LRAS curve?
A movement along the LRAS curve means only the price level changes while real (full-employment) output stays at potential GDP—think of moving up or down the vertical LRAS because AD changed in the long run and wages/prices fully adjusted (EK MOD-2.I.1). A shift of the LRAS curve means the economy’s potential output itself changes: LRAS shifts right if resources, labor supply, capital, or productivity grow (or tech improves); it shifts left if productive capacity falls (EK MOD-2.I.2). For AP free-response, remember: short-run AD or SRAS shocks cause movements off full employment, but long-run self-adjustment (flexible wages/prices) moves the economy back along AD to the vertical LRAS unless LRAS itself has shifted. For a quick review, see the Topic 3.7 study guide (https://library.fiveable.me/ap-macroeconomics/unit-3/long-run-self-adjustment/study-guide/VeYA6gFFsLYxu92do3Od) and try practice problems (https://library.fiveable.me/practice/ap-macroeconomics).
Why do some economists think the government shouldn't intervene if the economy self-adjusts anyway?
Some economists argue the government shouldn’t intervene when the economy can self-adjust because of how the long-run self-correction works and the costs/risks of policy. If wages and prices are flexible, SRAS will shift back and restore full-employment (the natural rate) after a demand shock (EK MOD-2.I.1). Intervention risks crowding out private spending, creating higher long-run inflation, and often suffers from recognition, implementation, and impact lags that can make policy destabilizing. Practically, policymakers can overshoot—fixing short-run gaps but leaving worse inflation or debt later. For the AP exam, you should be able to draw AD–SRAS–LRAS graphs and explain this self-correction (Topic 3.7). For a clear review, see the Fiveable long-run self-adjustment study guide (https://library.fiveable.me/ap-macroeconomics/unit-3/long-run-self-adjustment/study-guide/VeYA6gFFsLYxu92do3Od) and practice problems (https://library.fiveable.me/practice/ap-macroeconomics).
How do I analyze what happens when both AD and SRAS shift at the same time in the long run?
Quick way to handle simultaneous AD and SRAS shifts for the long run: 1. Identify the short-run moves: note direction of AD (→ or ←) and SRAS (→ or ←). That tells you the short-run change in output and price level. 2. Remember EK MOD-2.I.1: in the long run, wages/prices are flexible so SRAS shifts over time to restore full-employment output (YF). So whatever the short-run output gap, SRAS will shift until AD intersects vertical LRAS at YF. 3. Final real output in the long run = potential output (YF) unless LRAS itself changes. If LRAS shifts (productivity, resources), long-run output changes (EK MOD-2.I.2). 4. The long-run price level is where the new AD curve crosses LRAS. So AD mainly determines the final PL; SRAS adjustment just gets output back to YF. Example: AD right, SRAS left → short run: ambiguous output, higher PL. Long run: SRAS shifts (wage changes) so output returns to YF; final PL is above original if AD net > original (AD sets price), unless LRAS moved. On the exam you should draw an AD–SRAS–LRAS graph showing short-run and long-run adjustments (Skill 4 tasks). For a topic review, see the Long-Run Self-Adjustment study guide (https://library.fiveable.me/ap-macroeconomics/unit-3/long-run-self-adjustment/study-guide/VeYA6gFFsLYxu92do3Od) and do more practice problems (https://library.fiveable.me/practice/ap-macroeconomics).