## _wp0869

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---

### I. INTRODUCTION
- Research question: What are the macroeconomic effects of fiscal policy, and how can fiscal policy help achieve a soft landing for an overheated economy?
- Context for Colombia:
  - Real GDP growth estimated at 6.8 percent in 2006; Fund staff project 6.8 percent for 2007.
  - Average CPI inflation expected to rise 1 percentage points to 5½ percent in 2007.
  - Banco de la República’s policy interest rate increased by 350 basis points from 6 percent in April 2006 to 9½ percent in November 2007.
  - External current account deficit projected to double to about 4 percent of GDP in 2007.
  - Output estimated about 3 percent above potential as of Q2 2007.
  - Growth projected to slow to about 5 percent in 2008, with a positive output gap remaining.
- Paper’s approach:
  - Uses the Global Integrated Monetary and Fiscal (GIMF) model (Kumhof and Laxton, 2007a).
  - Focuses on: (i) stronger fiscal response reducing burden on monetary policy; (ii) fiscal response inducing inflation-output volatility tradeoff; (iii) interaction of fiscal effectiveness with monetary response and fiscal implementation lags.

### II. METHODOLOGY — Model Structure and Key Equations
- Model overview:
  - GIMF: open economy general equilibrium model with non-Ricardian features, nominal and real rigidities, monetary and fiscal reaction functions.
  - Ricardian equivalence does not hold for four reasons:
    - Overlapping generations (OLG) with finite lifetimes; households myopic and perceive debt-financed tax cuts as increased human wealth.
    - Life-cycle worker productivity declining with age; future payroll tax increases discounted.
    - Liquidity-constrained consumers (LIQ) who change consumption one-for-one with after-tax income.
    - Distortionary payroll and capital income taxes.
  - Public capital is productive and enhances private factor productivity.
  - Real rigidities: consumption habits, investment adjustment costs, import adjustment costs.
  - Nominal rigidities: sticky inflation Phillips curves in each sector.
- Fiscal rule for fiscal balance-to-GDP ratio:
  - Rule: fbal_t/gdp_t = φ* + d*(τ_t − τ*_t).
  - Interpretations of d:
    - d = 0: fiscal balance kept equal to φ* (excess tax revenue spent) — defined as procyclical (balanced budget).
    - d < 0: procyclical.
    - d = 1: structural balance rule (1 percentage point of GDP increase in excess tax revenue → 1 percentage point increase in fiscal balance).
    - d > 1: countercyclical (improvement in fiscal balance > increase in excess revenue).
- Monetary policy:
  - Inflation forecast-based rule consistent with BdR’s MMT; includes 4-quarter inflation forecast, inflation target π*, coefficient i_μ denotes nominal interest rate inertia.
  - Monetary policy responds to output only insofar as it forecasts inflation.
- Endogenous country-specific risk premium:
  - UIP equation for foreign currency bonds: RW_t i + E_t ε_{t+1} = (1 + i_t)/(1 + ρ_t).
  - Risk premium non-linear form: ρ_t = δ_1 + δ_2 * max[0, (debt_t/gdp_t − debt_max/gdp)]^{δ_3}.
  - Properties:
    - If δ_2 = 0 → risk premium equals exogenous δ_1 regardless of debt ratio.
    - If δ_2 > 0 → decline in government debt reduces risk premium; as debt rises toward debt_max/gdp, premium rises at increasing rate.
    - δ_3 > 0 determines curvature.

### III. CALIBRATION
- Countries and periodicity:
  - Two countries: Colombia and rest of the world.
  - Each period = one quarter.
  - Colombia = 0.3 percent of world GDP.
  - Steady-state inflation rates: Colombia 3 percent per year; rest of world 2 percent per year.
  - Steady-state technological progress: 2 percent per year.
  - Population growth: 1 percent per year.
  - Real interest in rest of world (initial steady state): 3 percent per year.
- Household parameters:
  - Planning horizon: 15 years → probability of death = 6.7 percent per year.
  - Decline in lifecycle worker productivity: 5 percent per year.
  - Liquidity-constrained households: 50 percent of Colombian households (same as Chile calibration; U.S. comparison given as 33 percent).
- Public capital and investment:
  - Elasticity of aggregate output w.r.t. public capital set to 0.14.
  - Calibration: 10 percent real increase in public investment → long-run increase in real GDP net of depreciation of about 1.4 percent.
  - Depreciation of public capital: 4 percent per year.
- Fiscal policy response parameter d:
  - Range considered: from strongly procyclical d = −0.5 to strongly countercyclical d = 4.5.
  - Fiscal rule implemented by adjusting payroll, consumption, and capital income tax rates proportionally.
- Steady-state fiscal and debt targets:
  - Fiscal balance stabilizes debt-to-GDP ratio at projected end-2007 level of 38 percent.
  - Example: if steady-state nominal growth rate = 6 percent and debt-to-GDP = 38 percent, steady-state debt-stabilizing fiscal deficit equals 2.2 percent of GDP (2.2− = φ*).
  - A decline in the fiscal deficit by 0.5 percentage points of GDP associated with long-run decline in debt-to-GDP ratio of 8.8 percentage points (8.8 = 0.5 × (1.06/0.06)).
- Monetary policy calibration:
  - Baseline inflation response parameter π_μ = 5.1.
  - Sensitivity checks: less aggressive π_μ = 0.25; more aggressive π_μ = 4.
  - Nominal interest rate inertia parameter i_μ = 0.5.
- Risk premium elasticity calibration:
  - Empirical guidance: 1 percentage point increase in debt-to-GDP associated with increase in EMBI spread of 7–8.26 basis points.
  - Baseline calibration: at end-2007 position, 1 percentage point increase in debt-to-GDP raises risk premium by 8 basis points.
  - Example: raising debt ratio from 38 percent to 43 percent of GDP increases risk premium by about 40 basis points.

### IV. RESULTS: MACROECONOMIC EFFECTS OF FISCAL POLICY TIGHTENING
- Experiment: permanent improvement in fiscal balance by 0.5 percentage points of GDP.
  - Base case: consolidation implemented by cutting public consumption by 0.5 percentage points of GDP (equivalent to a permanent 3 percent cut in real government consumption as baseline experiment).
  - Results reported as deviations from baseline steady state.
- Base-case qualitative finding:
  - Fiscal consolidation via cut in government consumption associated with a short-run decline in aggregate demand and a medium-term increase in GDP.
  - On impact, overall fiscal balance-to-GDP ratio improves by 0.5 percentage points.
  - As debt and associated interest costs decline, taxes are reduced to keep overall fiscal balance unchanged at the new level.
- Effects of the permanent 0.5 percentage points of GDP fiscal consolidation (cut in government consumption):
  - Fiscal balance improvement: 0.5 percentage points of GDP above the initial position.
  - Reduction in government debt-to-GDP ratio: eventually 8.8 percentage points.
  - Short-run output response:
    - Real GDP declines by 0.58 percent on impact.
    - Implied short-run multiplier: 1.15 (0.58 percent impact / 0.5 percent-of-GDP cut).
  - Monetary policy reaction:
    - Reduces interest rates in response to decline in expected inflation.
    - Stimulates private spending and contributes to real depreciation.
  - External sector:
    - Current account improves by 0.36 percentage points of GDP within the first year.
    - Net foreign assets increase as overall Colombian savings rise.
  - Long-run output:
    - Permanent improvement of the fiscal balance by 0.5 percent of GDP that reduces the debt-to-GDP ratio by, eventually, 8.8 percentage points raises real GDP in the long-run by 0.56 percent.

### Sensitivity analysis — composition of fiscal tightening
- Cutting productive public investment by 0.5 percentage points of GDP:
  - Aggregate demand contraction of 0.62 percent on impact.
  - Long-run GDP declines by 0.86 percent due to reduced supply capacity.
  - If public investment is not productive, cuts in capital expenditure produce effects broadly similar to reductions in public consumption.
- Alternative consolidation instruments (all sized 0.5 percent of GDP):
  - Payroll tax increase of 0.5 percent of GDP: GDP lowers by 0.39 percent after three quarters (multiplier of 0.78 after three quarters).
  - Increase in consumption taxes of 0.5 percent of GDP: GDP falls by 0.24 percent in the first year.
  - Cut in lump-sum transfers of 0.5 percent of GDP: GDP declines by 0.17 percent within the first year.
- Interpretation:
  - Short-run contractionary effects are smaller and more gradual when consolidation is implemented via tax increases or transfer cuts than when cutting government purchases.
  - Using savings from lower debt-interest payments to lower distortionary taxes or increase productive public investment produces stronger long-run output gains than cuts in government consumption alone.

### Fiscal policy and macroeconomic stability — shock types and fiscal response strength
- Shock types analyzed:
  - Demand shock: reduction in private savings (4 percentage point increase in the consumer rate of time preference; AR(1) with persistence 0.9; half-life ~7 quarters).
  - Supply shock: increase in firms’ markups (5 percentage point increase in markup in the distribution sector; AR(1) persistence 0.9; half-life ~7 quarters).
  - Risk premium shock: exogenous 100 basis-point fall in the exogenous risk premium component 1δ; AR(1) persistence 0.9.
- Demand shock findings:
  - Stronger fiscal response (larger d) stabilizes output and inflation and reduces the burden on monetary policy.
  - Smaller interest rate increases are required; exchange rate appreciates less; external current account deteriorates less and converges more smoothly.
- Supply shock findings:
  - Fiscal response to excess tax revenue induces an inflation-output volatility tradeoff: fiscal loosening moderates output decline but slightly raises inflation.
  - Under baseline calibration (strong monetary response), the output-inflation volatility tradeoff is modest.
  - Efficiency frontier result:
    - A 1 percent decline in output volatility is associated with an increase in inflation volatility of about 0.2 percent (range of fiscal response parameters considered).
  - Monetary policy sensitivity:
    - With weak monetary response (μπ = 0.25) versus aggressive response (μπ = 4), the efficiency frontier is twice as steep with weak monetary response.
- Risk premium shock findings:
  - A 100 basis-point fall in the risk premium:
    - Induces real appreciation, increases investment and consumption, and deteriorates external current account.
    - Raises demand for Colombian assets via increase in risk-adjusted return on Colombian bonds (1 + it + ρt).
    - Investment response is hump-shaped due to quadratic investment adjustment costs.
    - Initial appreciation has disinflationary effect; monetary easing follows.
  - Stronger fiscal response (larger d) moderates increase in output, slightly lowers inflation, moderates exchange rate appreciation, and reduces deterioration in current account balance.

### Sensitivity analysis — fiscal policy implementation lags
- Fiscal response with implementation lag L quarters (fiscal surplus responds with lag L to excess tax revenue).
- Findings:
  - Implementation lags of 1 or 2 quarters: countercyclical fiscal policy continues to enhance macroeconomic stability, though less than with no lags.
  - Implementation lags of 3 quarters or more: an aggressive response to excess tax revenue (d > 1) can be counter-productive and destabilize output.

### Summary of quantitative policy-relevant results
- Fiscal consolidation size analyzed: 0.5 percentage points of GDP.
- Debt-to-GDP reduction: eventually 8.8 percentage points.
- Short-run GDP impact (varies by composition):
  - Government consumption cut (impact): −0.58 percent.
  - Public investment cut (impact): −0.62 percent; long-run −0.86 percent.
  - Payroll tax increase (0.5 percent of GDP): −0.39 percent after three quarters.
  - Consumption tax increase (0.5 percent of GDP): −0.24 percent in first year.
  - Lump-sum transfer cut (0.5 percent of GDP): −0.17 percent within first year.
- Long-run GDP gain from consolidation based on cuts in government consumption: 0.56 percent.
- Current account improvement within first year after consumption cut: 0.36 percentage points of GDP.
- Demand-shock specification: 4 percentage point increase in consumer rate of time preference; AR(1) persistence 0.9 (half-life ≈ 7 quarters).
- Supply-shock specification: 5 percentage point increase in markup; AR(1) persistence 0.9 (half-life ≈ 7 quarters).
- Risk-premium shock specification: temporary 100 basis-point fall; AR(1) persistence 0.9.

### Policy implications and recommendations
- Composition matters:
  - Favor consolidation via reductions in transfers or increases in taxes over cuts in productive public investment if long-run output preservation is a priority.
  - Use savings from lower debt-interest payments to lower distortionary taxes or to increase productive public investment to maximize long-run output gains.
- Coordinate fiscal and monetary policy:
  - A strong monetary policy commitment to stabilizing inflation expectations reduces the inflationary cost of accommodative fiscal responses during supply shocks.
  - A stronger fiscal response to excess tax revenue can lessen the burden on monetary policy during demand-driven overheats.
- Act promptly:
  - Limit fiscal implementation lags to at most 1–2 quarters for countercyclical fiscal policy to remain stabilizing; avoid aggressive delayed responses (lags ≥ 3 quarters) that can destabilize output.

*IMF Working Paper content extracted from the provided document.*

### References..............................................................................................................

### _wp0869 - References..............................................................................................................

### I. INTRODUCTION
- Research question: What are the macroeconomic effects of fiscal policy, and how can fiscal policy help achieve a soft landing for an overheated economy?
- Context for Colombia:
  - Real GDP growth estimated at 6.8 percent in 2006; Fund staff project 6.8 percent for 2007.
  - Average CPI inflation expected to rise 1 percentage points to 5½ percent in 2007.
  - Banco de la República’s policy interest rate increased by 350 basis points from 6 percent in April 2006 to 9½ percent in November 2007.
  - External current account deficit projected to double to about 4 percent of GDP in 2007.
  - Output estimated about 3 percent above potential as of Q2 2007.
  - Growth projected to slow to about 5 percent in 2008, with a positive output gap remaining.
- Paper’s approach:
  - Uses the Global Integrated Monetary and Fiscal (GIMF) model (Kumhof and Laxton, 2007a).
  - Focuses on: (i) stronger fiscal response reducing burden on monetary policy; (ii) fiscal response inducing inflation-output volatility tradeoff; (iii) interaction of fiscal effectiveness with monetary response and fiscal implementation lags.

### II. METHODOLOGY — Model Structure and Key Equations
- Model overview:
  - GIMF: open economy general equilibrium model with non-Ricardian features, nominal and real rigidities, monetary and fiscal reaction functions.
  - Ricardian equivalence does not hold for four reasons:
    - Overlapping generations (OLG) with finite lifetimes; households myopic and perceive debt-financed tax cuts as increased human wealth.
    - Life-cycle worker productivity declining with age; future payroll tax increases discounted.
    - Liquidity-constrained consumers (LIQ) who change consumption one-for-one with after-tax income.
    - Distortionary payroll and capital income taxes.
  - Public capital is productive and enhances private factor productivity.
  - Real rigidities: consumption habits, investment adjustment costs, import adjustment costs.
  - Nominal rigidities: sticky inflation Phillips curves in each sector.
- Fiscal rule for fiscal balance-to-GDP ratio:
  - Rule: fbal_t/gdp_t = φ* + d*(τ_t − τ*_t)  (as described in text — fiscal balance responds to excess tax revenue via parameter d).
  - Definitions and interpretations of d:
    - d = 0: fiscal balance kept equal to φ* (excess tax revenue spent) — defined as procyclical (balanced budget).
    - d < 0: procyclical.
    - d = 1: structural balance rule (1 percentage point of GDP increase in excess tax revenue → 1 percentage point increase in fiscal balance).
    - d > 1: countercyclical (improvement in fiscal balance > increase in excess revenue).
- Monetary policy (inflation forecast-based rule):
  - Monetary rule specification consistent with BdR’s MMT; includes 4-quarter inflation forecast, inflation target π*, coefficient i_μ denotes nominal interest rate inertia.
  - Monetary policy responds to output only insofar as it forecasts inflation.
- Endogenous country-specific risk premium:
  - UIP equation for foreign currency bonds: (1) RW_t i + E_t ε_{t+1} = (1 + i_t)/(1 + ρ_t) (as presented in text).
  - Risk premium non-linear form: ρ_t = δ_1 + δ_2 * max[0, (debt_t/gdp_t − debt_max/gdp)]^{δ_3} (as represented in text).
  - Properties:
    - If δ_2 = 0 → risk premium equals exogenous δ_1 regardless of debt ratio.
    - If δ_2 > 0 → decline in government debt reduces risk premium; as debt rises toward debt_max/gdp, premium rises at increasing rate.
    - δ_3 > 0 determines curvature.

### III. CALIBRATION
- Countries and periodicity:
  - Two countries: Colombia and rest of the world.
  - Each period = one quarter.
  - Colombia = 0.3 percent of world GDP.
  - Steady-state inflation rates: Colombia 3 percent per year; rest of world 2 percent per year.
  - Steady-state technological progress: 2 percent per year.
  - Population growth: 1 percent per year.
  - Real interest in rest of world (initial steady state): 3 percent per year.
- Household parameters:
  - Planning horizon: 15 years → probability of death = 6.7 percent per year.
  - Decline in lifecycle worker productivity: 5 percent per year.
  - Liquidity-constrained households: 50 percent of Colombian households (same as Chile calibration; U.S. comparison given as 33 percent).
- Public capital and investment:
  - Elasticity of aggregate output w.r.t. public capital set to 0.14 (Ligthart and Suárez, 2005).
  - Calibration: 10 percent real increase in public investment → long-run increase in real GDP net of depreciation of about 1.4 percent.
  - Depreciation of public capital: 4 percent per year.
- Fiscal policy response parameter d:
  - Range considered: from strongly procyclical d = −0.5 to strongly countercyclical d = 4.5.
  - Fiscal rule implemented by adjusting payroll, consumption, and capital income tax rates proportionally.
- Steady-state fiscal and debt targets:
  - Fiscal balance stabilizes debt-to-GDP ratio at projected end-2007 level of 38 percent.
  - Steady-state relationship: fdef = (gdp/debt) * (NG/(1+NG)) — as given in text (equation form described).
  - Example: if steady-state nominal growth rate = 6 percent and debt-to-GDP = 38 percent, steady-state debt-stabilizing fiscal deficit equals 2.2 percent of GDP (2.2− = φ*).
  - A decline in the fiscal deficit by 0.5 percentage points of GDP associated with long-run decline in debt-to-GDP ratio of 8.8 percentage points (calculation noted: 8.8 = 0.5 × (1.06/0.06)).
- Monetary policy calibration:
  - Baseline inflation response parameter π_μ = 5.1.
  - Sensitivity checks: less aggressive π_μ = 0.25; more aggressive π_μ = 4.
  - Nominal interest rate inertia parameter i_μ = 0.5.
- Risk premium elasticity calibration:
  - Empirical guidance: Rowland and Torres (2004) find 1 percentage point increase in debt-to-GDP associated with increase in EMBI spread of 7–8.26 basis points.
  - Baseline calibration: at end-2007 position, 1 percentage point increase in debt-to-GDP raises risk premium by 8 basis points.
  - Example: raising debt ratio from 38 percent to 43 percent of GDP increases risk premium by about 40 basis points (calibration consistent with observed Colombia EMBI change from 2006 to 2007).
- Figure referenced:
  - Figure 1. Domestic Risk Premium and the Debt-to-GDP Ratio (plot showing government debt in percent of GDP on x-axis and risk premium in percent p.a. on y-axis).

### IV. RESULTS: MACROECONOMIC EFFECTS OF FISCAL POLICY TIGHTENING
- Experiment: permanent improvement in fiscal balance by 0.5 percentage points of GDP.
  - Base case: consolidation implemented by cutting public consumption by 0.5 percentage points of GDP (equivalent to a permanent 3 percent cut in real government consumption as baseline experiment).
  - Results reported as deviations from baseline steady state (i.e., steady state without consolidation).
- Base-case qualitative finding:
  - Fiscal consolidation via cut in government consumption:
    - Associated with a short-run decline in aggregate demand.
    - Associated with a medium-term increase in GDP.
  - On impact, overall fiscal balance-to-GDP ratio improves by 0.5 percentage points.
  - As debt and associated interest costs decline, taxes are reduced to keep overall fiscal balance unchanged at the new level (statement continued in source beyond provided excerpt).

*Source: IMF working paper content in the supplied PDF excerpt.*

### 0.5 percentage points of GDP above the initial position. The improvement in the fiscal

### _wp0869 - 0.5 percentage points of GDP above the initial position. The improvement in the fiscal

### Effects of a permanent 0.5 percentage points of GDP fiscal consolidation (cut in government consumption)
- Fiscal balance improvement: 0.5 percentage points of GDP above the initial position.
- Reduction in government debt-to-GDP ratio: eventually 8.8 percentage points.
- Short-run output response:
  - Real GDP declines by 0.58 percent on impact.
  - Implied short-run multiplier: 1.15 (0.58 percent impact / 0.5 percent-of-GDP cut).
- Monetary policy reaction:
  - Reduces interest rates in response to decline in expected inflation.
  - Stimulates private spending and contributes to real depreciation.
- External sector:
  - Current account improves by 0.36 percentage points of GDP within the first year.
  - Net foreign assets increase as overall Colombian savings rise.
- Long-run output:
  - A permanent improvement of the fiscal balance by 0.5 percent of GDP that reduces the debt-to-GDP ratio by, eventually, 8.8 percentage points raises real GDP in the long-run by 0.56 percent.

### Sensitivity analysis — composition of fiscal tightening
- Cutting productive public investment by 0.5 percentage points of GDP:
  - Aggregate demand contraction of 0.62 percent on impact.
  - Long-run GDP declines by 0.86 percent due to reduced supply capacity.
  - If public investment is not productive, cuts in capital expenditure produce effects broadly similar to reductions in public consumption.
- Alternative consolidation instruments (all sized 0.5 percent of GDP):
  - Payroll tax increase of 0.5 percent of GDP: GDP lowers by 0.39 percent after three quarters (multiplier of 0.78 after three quarters).
  - Increase in consumption taxes of 0.5 percent of GDP: GDP falls by 0.24 percent in the first year.
  - Cut in lump-sum transfers of 0.5 percent of GDP: GDP declines by 0.17 percent within the first year.
- Interpretation:
  - Short-run contractionary effects are smaller and more gradual when consolidation is implemented via tax increases or transfer cuts than when cutting government purchases.
  - Using savings from lower debt-interest payments to lower distortionary taxes or increase productive public investment produces stronger long-run output gains than cuts in government consumption alone.

### Fiscal policy and macroeconomic stability — shock types and fiscal response strength
- Shock types analyzed:
  - Demand shock: reduction in private savings (4 percentage point increase in the consumer rate of time preference; AR(1) with persistence 0.9; half-life ~7 quarters).
  - Supply shock: increase in firms’ markups (5 percentage point increase in markup in the distribution sector; AR(1) persistence 0.9; half-life ~7 quarters).
  - Risk premium shock: exogenous 100 basis-point fall in the exogenous risk premium component 1δ; AR(1) persistence 0.9.
- Demand shock findings:
  - Stronger fiscal response (larger values of parameter d) stabilizes output and inflation and reduces the burden on monetary policy.
  - Smaller interest rate increases are required; exchange rate appreciates less; external current account deteriorates less and converges more smoothly.
- Supply shock findings:
  - Fiscal response to excess tax revenue induces an inflation-output volatility tradeoff: fiscal loosening moderates output decline but slightly raises inflation.
  - Under baseline calibration (strong monetary response), the output-inflation volatility tradeoff is modest.
  - Efficiency frontier result (range of fiscal response parameters considered: ]5.4,5.0[−∈d):
    - A 1 percent decline in output volatility is associated with an increase in inflation volatility of about 0.2 percent.
  - Monetary policy sensitivity:
    - With weak monetary response (μπ = 0.25) versus aggressive response (μπ = 4), the efficiency frontier is twice as steep with weak monetary response; weaker monetary policy substantially increases inflationary consequences of accommodative fiscal response.
- Risk premium shock findings:
  - A 100 basis-point fall in the risk premium:
    - Induces real appreciation, increases investment and consumption, and deteriorates external current account.
    - Raises demand for Colombian assets via increase in risk-adjusted return on Colombian bonds (1 + it + ρt).
    - Investment response is hump-shaped due to quadratic investment adjustment costs.
    - Initial appreciation has disinflationary effect; monetary easing follows.
  - Stronger fiscal response (larger d) moderates increase in output, slightly lowers inflation, moderates exchange rate appreciation, and reduces deterioration in current account balance.

### Sensitivity analysis — fiscal policy implementation lags
- Fiscal response with implementation lag L quarters (fiscal surplus responds with lag L to excess tax revenue).
- Findings:
  - Implementation lags of 1 or 2 quarters: countercyclical fiscal policy continues to enhance macroeconomic stability, though less than with no lags.
  - Implementation lags of 3 quarters or more: an aggressive response to excess tax revenue (d > 1) can be counter-productive and destabilize output.

### Summary of quantitative policy-relevant results
- Fiscal consolidation size analyzed: 0.5 percentage points of GDP.
- Debt-to-GDP reduction: eventually 8.8 percentage points.
- Short-run GDP impact (varies by composition):
  - Government consumption cut (impact): −0.58 percent.
  - Public investment cut (impact): −0.62 percent; long-run −0.86 percent.
  - Payroll tax increase (0.5 percent of GDP): −0.39 percent after three quarters.
  - Consumption tax increase (0.5 percent of GDP): −0.24 percent in first year.
  - Lump-sum transfer cut (0.5 percent of GDP): −0.17 percent within first year.
- Long-run GDP gain from consolidation based on cuts in government consumption: 0.56 percent.
- Current account improvement within first year after consumption cut: 0.36 percentage points of GDP.
- Demand-shock specification: 4 percentage point increase in consumer rate of time preference; AR(1) persistence 0.9 (half-life ≈ 7 quarters).
- Supply-shock specification: 5 percentage point increase in markup; AR(1) persistence 0.9 (half-life ≈ 7 quarters).
- Risk-premium shock specification: temporary 100 basis-point fall; AR(1) persistence 0.9.

### Policy implications and recommendations (based on model experiments)
- Composition matters: favor consolidation via reductions in transfers or increases in taxes over cuts in productive public investment if long-run output preservation is a priority.
- Use savings from lower debt-interest payments to lower distortionary taxes or to increase productive public investment to maximize long-run output gains.
- Coordinate fiscal and monetary policy:
  - A strong monetary policy commitment to stabilizing inflation expectations reduces the inflationary cost of accommodative fiscal responses during supply shocks.
  - A stronger fiscal response to excess tax revenue can lessen the burden on monetary policy during demand-driven overheats.
- Act promptly:
  - Limit fiscal implementation lags to at most 1–2 quarters for countercyclical fiscal policy to remain stabilizing; avoid aggressive delayed responses (lags ≥ 3 quarters) that can destabilize output.

*IMF Working Paper content extracted from the provided document.*

---


_Source: https://www.imf.org/-/media/websites/imf/imported-full-text-pdf/external/pubs/ft/wp/2008/_wp0869.pdf_