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---

### Introduction — fiscal situation and intergenerational stakes
- Recent fiscal metrics:
  - Primary deficit has been “about 8 percent of GDP” in recent years.
  - General government gross debt reached “over 220 percent of GDP by end-2011.”
  - Structural (cyclically adjusted) primary deficit estimated to have “exceeded 7 percent of GDP in 2011.”
  - Putting public debt-to-GDP on a downward path would require consolidation of “about 10 percentage points of GDP over the next decade.”
- Intergenerational resource inequality:
  - Cabinet Office (2003) estimate: PDV of the lifetime net burden for future generations would be “100 million yen per household (about 20 times household annual disposable income)” more than for those aged 60 years or older.
- Private transfers evidence:
  - Senior generations do not display sufficient altruistic transfers to offset intergenerational imbalance (Horioka, 2002).
  - Rich households tend to receive larger gifts and inheritances (Hamaaki, Hori, and Murata, 2012).

### Key policy conclusion and trade-offs
- Principal policy message:
  - “Combining social security spending reforms and revenue measures in a balanced manner would be the fairest way to distribute the burden of fiscal consolidation across the generations.”
- Rationale and cautions:
  - Social security spending (pension and nonpension) drives large deficits; social security reforms are natural consolidation targets.
  - OLG simulations show social security spending reforms have a less adverse effect on intergenerational inequality than many alternatives.
  - Excessive reliance on social security cuts—particularly cutting pension benefits for current pensioners—would “have a serious impact on the welfare of seniors,” arguing for balance with revenue measures.
- Timing:
  - “Delaying consolidation would increase the burden for young and future generations while reducing that for current senior generations.”

### Model specification and key numerical assumptions
- Model framework:
  - Standard lifecycle overlapping generations (OLG) model with perfect foresight and endogenous labor supply; no uncertainty; one representative agent per generation.
  - Sectors: household, corporate, government.
- Household specifics:
  - Life span D = “60 years” (generations numbered 60); start at age 20 with zero assets; end at age 79 without bequests.
  - Pension eligibility age: agents aged 65 years and older eligible for public pension benefits.
- Government and fiscal rule:
  - Revenue sources: personal income tax, social security contributions, VAT; pay-as-you-go pension system with fraction of benefits funded by tax revenue.
  - Baseline structural primary balance path: improves by “10 percentage points of GDP from –6.5 percent in year T – 1 to 3.5 percent in year T + 8.”
    - Note: “The current period is year T. If 2012 is considered to be year T, year T + 8 corresponds to 2020.”
  - Cyclical factors set to zero so structural and primary balances coincide.
- Demographics:
  - Growth rate of generation size for newborns set at “–0.75 percent” in the transition phase (between T – 10 and T + 59) and “0 percent” for newborns in year T + 60 and thereafter.

### Model limitations and interpretation caveats
- Simplifications:
  - Nonpension social security benefits and other government spending treated as exogenous and do not enter household utility.
  - No uncertainty about pensions, wages, or life length; no within-generation heterogeneity.
  - Assumption of guaranteed future pension payments irrespective of fiscal sustainability in the model.
- Implication:
  - Results informative about general-equilibrium and intergenerational allocation effects but abstract from uncertainty and intra-cohort distributional heterogeneity.

### OLG simulation — compared fiscal adjustment measures (section 12)
- Measures compared (each permanent, each improving structural primary balance by 0.5 percent of GDP):
  1. Reducing pension replacement ratio (maintaining pension eligibility age).
  2. Raising pension eligibility age.
  3. Raising pension contribution rate.
  4. Containing nonpension social security benefits.
  5. Raising VAT rate.
- Implementation timing:
  - Each measure implemented immediately in year T + 3, except measure (2) where eligibility age rises gradually starting in T + 3.
- Key comparative findings on intergenerational burden and fairness:
  - Reducing replacement ratio (to save 0.5 percent of GDP) modeled as ~5 percent reduction in replacement ratio in year T + 3 (from 40 percent to 38 percent of average wage before taxes), affecting immediately all generations receiving pensions; assumed disproportionately larger reduction for higher income households.
  - Raising eligibility age modeled as: basic pension age 65 → 66 in T + 3 and → 67 in T + 5; imposes zero burden on generations already aged 65 or older.
  - Bottom line: Reducing the replacement ratio applied immediately to all beneficiaries would be fairer in intergenerational equality terms than increasing the eligibility age.
  - Raising pension contribution rate or personal income tax worsens intergenerational imbalance relative to reducing replacement ratio; younger generations bear larger lifetime burden because working generations pay higher contributions/taxes.
  - Raising pension contribution rate has greater distortionary impact on labor supply and capital accumulation, reducing output more than a VAT increase.
  - Containing nonpension social security benefits increases lifetime burden more equally across generations than reducing pension benefits or raising pension contributions — a middle option.
  - Raising VAT rate raises burden relatively equally across generations compared to lower pension benefits or higher pension contributions; macro effect dampens aggregate output but less than raising pension contribution rate.
    - Caveat: real-world VAT increase would raise CPI and thus nominal pension benefits linked to CPI; paper assumes VAT increase does not change replacement ratio (interpretation: VAT increase combined with reduced pace of pension benefit increases).
  - Behavioral note: ~60 percent of consumption of those aged over 65 years is financed by past savings.
- Summary qualitative judgments (verbatim labels):
  - 1) Reducing pension replacement ratio: ＋ (more intergenerationally fair)
  - 2) Raising pension eligibility age: (presented as intermediate)
  - 3) Raising pension contribution rate/personal income tax rate: －－ (worse for fairness and aggregate economy)
  - 4) Containing nonpension social security benefits: － (less negative than measure 3)
  - 5) Raising VAT rate: － (but less negative than measure 3)

### Macroeconomic implications (selected quantitative outcomes)
- Relative GDP and saving effects (deviations relative to raising the pension eligibility age, policy in year T + 3):
  - Raising pension contribution rate → larger negative deviation in GDP level and saving rate (years T+3 through T+6) than raising VAT rate.
- Empirical consistency:
  - Finding consistent with OECD evidence that growth is moderately, but negatively correlated with burden from social security contributions and employee income tax.

### Assessment of consolidation packages (10 percentage points of GDP total structural adjustment)
- Two illustrative options (improving the structural primary balance by 10 percentage points between year T-1 and T+8):
  - Option (1): 1.5 percentage points of savings from social security benefits (0.5 in pension benefits and 1.0 in nonpension social security benefits) + 8.5 percentage points of revenue and nonsocial security adjustment.
    - Option (1a): Reducing pension replacement ratio generates 0.5 percentage points of GDP savings from pension reform.
    - Option (1b): Raising pension eligibility age generates 0.5 percentage points of GDP savings from pension reform.
  - Option (2): 10 percentage points of revenue and nonsocial security adjustment (no social security reforms).
- Distributional consequences:
  - Increase in lifetime burden overwhelmingly larger for young generations under both options.
  - Example: PDV impact for those aged 20 amounts to about 500 percent of current (year T) per household wage income before taxes (i.e., as large as 5 years of the current per household wage income).
  - Option (1) reduces the PDV net burden of those aged 20 by about 15 percentage points of current per household wage income before taxes, relative to option (2).
  - Including reduction in replacement ratio (1a) increases burden for current pensioners more and thus corrects intergenerational imbalance more than increasing eligibility age (1b).
- Interpretation:
  - Including social security spending reforms in a fiscal consolidation package helps correct intergenerational imbalance, though benefit for the young may be modest.
  - Excessive reliance on across-the-board replacement ratio cuts could push low-income retirees below the relative poverty line; argues for balanced combination of social security reforms and revenue measures.
  - VAT increase impact on output and intergenerational equity would be less adverse than raising pension contributions.

### Effects of a 10 percentage point adjustment combined with social security reforms (section 15)
- Aggregate lifetime net burden (right-hand side of Figure 4; year T set at 2012):
  - For those aged 20–29: total net PDV burden = 1600 percent of current per household wage income before taxes.
    - This is nearly 40 percent higher than net burden implied by 2003 policy estimates without the 10 percentage point adjustment.
  - For those aged 70 or higher: increase in burden due to adjustment minimal relative to net benefits implied by 2003 estimates.
  - For those aged 60–69: net burden larger but total net burden remains negative.
- Timing of consolidation — baseline and delay scenarios:
  - Baseline: 10 percentage point improvement between year T – 1 and T + 8, consolidation starting gradually in year T.
  - Delay scenario: start delayed by 3 years to year T + 3 (consolidation through T + 11).
    - If maintaining same 10 percentage points:
      - Lifetime burden smaller for all generations initially and GDP higher relative to no-delay, but higher deficits raise public debt and eventually crowd out output through higher interest rates.
      - Costs of crowding-out increase with longer delay; net public debt reaches nearly 300 percent of GDP in year T + 60 (end-life of those aged 20 in year T).
    - If targeting same debt-to-GDP by year T + 60 as no-delay:
      - Overall adjustment must be larger by about 1 percentage point of GDP.
      - Increase in PDV lifetime burden for those aged 20 would be larger by 20 percentage points of current per household wage before taxes, assuming additional savings arise from nonsocial security spending.
      - Increase much smaller for senior generations relative to no-delay, exacerbating intergenerational imbalance.
- Conclusion on timing:
  - Timing of consolidation is as quantitatively important as composition; delaying fiscal consolidation can be costly and worsen intergenerational inequality.
- Political economy:
  - Delay lowers burden for older generations, complicating early consolidation politically in Japan given high share of middle-aged and senior voters.
  - Proposal: independent body to ensure fair intergenerational resource distribution has been proposed but is politically challenging.

### Policy options to correct intergenerational resource imbalance
- Greater immigration:
  - Baseline assumption: generation size declines by 0.75 percent every year between T – 10 and T + 60.
  - OLG simulation: if immigration keeps size of newly-joining generation constant from year T + 1 onward, per household lifetime burden of those currently aged 20 for financing pension benefits would decline by 20 percentage points of current per household wage income (before taxes) relative to no-immigration case (based on 10 percentage points of GDP consolidation).
  - Parameter implications: share of immigrants rises by 6 percentage points by year T + 30 and by 25 percentage points by year T + 60; share of immigrants in total population was ~2 percent in 2009.
- Raise productivity growth via structural reforms:
  - Higher productivity growth trims needed fiscal adjustment (given debt target), reducing younger generations’ burden.
- Expand transfers to young generations (education and child allowances):
  - Directly mitigate intergenerational imbalance and indirectly raise fertility and labor input.
  - Japan’s public education and family spending is the lowest among OECD economies.
  - Fiscal space limited; requires savings elsewhere or more revenue from senior generations (e.g., higher inheritance tax).
- Design and distributional considerations:
  - If additional savings arise from nonsocial security spending, lifetime burden impacts could concentrate on younger cohorts.
  - Poverty risks: across-the-board pension replacement cuts could increase poverty among low-income retirees; recommends targeted income transfers and excluding low-income/low-wealth households from benefit reductions — both requiring means testing and a tax identification system.
- Labor market interactions:
  - Concern: higher old-age labor participation might crowd out youth employment.
  - International evidence does not support crowding-out; Gruber, Milligan, and Wise (2009) report youth employment positively correlated with old-age employment (controlling for macro shocks).
  - OLG simulation: curbing pension benefits could encourage old-age labor participation and be relatively beneficial for young generations and aggregate growth.

### Box 1 — Public Pension System in Japan (key facts)
- Structure:
  - Two-layer system.
  - First layer: basic pension, flat-rate benefits (currently ¥66,000 per month).
    - As of 2012, those aged 65+ with ≥25 years of contributions eligible for basic pension.
    - Contribution mandatory for residents aged 20–59.
    - Those not eligible may receive separate public assistance if income and wealth below thresholds.
  - Second layer: defined-benefit pension proportional to income during contribution period; private company and government employees participate; second tier for self-employed is voluntary.
    - Male eligibility age for second tier will be gradually raised to 65 by 2025 from 60.
- Replacement ratios and fiscal size:
  - OECD (2011): replacement ratio for those currently at age 20 with average earnings ≈ 0.4 (lower than OECD average of 0.5).
  - FY2009 (April 2009 - March 2010) figures:
    - Aggregate public pension benefits ≈ ¥50 trillion (10 percent of GDP).
    - Government contributed ¥10 trillion to public pension, financing 50 percent of ¥20 trillion of basic pension benefits (first layer).
    - Aggregate pension benefits breakdown:
      - Second layer: Y28 trillion (6% of GDP)
      - First layer: Basic pension Y20 trillion (4% of GDP)

### Appendix I — Parameter values and key simulation assumptions (selected exact values)
- Calibrated parameters:
  - ρ = 0.8
  - γ = 0.75
  - θ = 0.5
  - β = 0.9995
  - Age profile of labor efficiency = Estimated from semi aggregate data; Log(labor efficiency) = 0.97101 + 0.048505*(age-20) -0.000915*(age-20)^2 (normalized average = 1)
  - Growth rate of population size in transition phase = -0.0075
  - α = 0.3
  - λ = 0.014
  - δ = 0.05
  - C-efficiency ratio = 0.7
  - Initial VAT rate = 0.1
  - Initial pension contribution rate + personal income tax rate = 0.2
  - Pension replacement ratio (to before tax average wage income) = 0.4
  - Share of basic pension benefits in total pension benefits = 0.4
  - Share of public debt crowding out private capital = 0.2
- Notes on parameters and sensitivity:
  - λ = 0.014 corresponds to total factor productivity growth of 0.01 (1 percent).
  - Japan’s narrowly defined VAT rate is 0.05 (5 percent); simulation uses initial VAT rate = 0.1 to capture other consumption taxation.
  - Example sensitivity: lowering generation growth rate from –0.75 percent to –1 percent raises lifetime burden for those aged 20 by 15 percentage points of current per household wage income before taxes.
- Baseline fiscal path (option (1a)):
  - Structural primary balance improves from –6.5 percent of GDP in year T – 1 (2011) to 3.5 percent of GDP in year T + 8 (2020).
  - Structural primary balance remains at 3.5 percent of GDP through year T + 99 (2111); adjusts in year T + 100 (2112) so net public debt to GDP ratio remains constant.
  - Total structural adjustment assumed = 10 percentage points of GDP between year T-1 and T+8.
- Perfect foresight:
  - Households expect exact path of future fiscal consolidation; alternative expectation scenarios change results little for total lifetime burden.

*Source: _wp12197 - References .........................................................................................................*

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

### _wp12197 - References .............................................................................................................

### Introduction — fiscal situation and intergenerational stakes
- Japan’s primary deficit has been “about 8 percent of GDP” in recent years, which pushed general government gross debt to “over 220 percent of GDP by end-2011.”
- The structural (cyclically adjusted) primary deficit is estimated to have “exceeded 7 percent of GDP in 2011.”
- Putting the public debt-to-GDP ratio firmly on a downward path would require consolidation of “about 10 percentage points of GDP over the next decade.”
- The pay-as-you-go social security system (pensions, health care, aged care) has already widened intergenerational resource inequality:
  - Cabinet Office (2003) estimate: the present discounted value (PDV) of the lifetime net burden for future generations would be “100 million yen per household (about 20 times household annual disposable income)” more than that for those aged 60 years or older.
- Empirical evidence on private transfers:
  - Senior generations in Japan do not display sufficient altruistic transfers to offset intergenerational imbalance (Horioka, 2002).
  - Rich (high income) households tend to receive larger gifts and inheritances (Hamaaki, Hori, and Murata, 2012).

### Key policy conclusion and trade-offs
- Principal policy message:
  - “Combining social security spending reforms and revenue measures in a balanced manner would be the fairest way to distribute the burden of fiscal consolidation across the generations.”
- Rationale and caveats:
  - Social security reforms are a natural consolidation target because rising social security benefits (pension and nonpension) are driving large deficits.
  - OLG simulations show social security spending reforms have a less adverse effect on intergenerational inequality than many alternatives.
  - Excessive reliance on social security cuts—particularly cutting pension benefits for current pensioners—would “have a serious impact on the welfare of seniors,” arguing for balance with revenue measures.
- Timing:
  - “Delaying consolidation would increase the burden for young and future generations while reducing that for current senior generations.”

### Simulation analysis — scenarios, impacts, and interpretation
- General interpretation:
  - Fiscal consolidation tends to worsen intergenerational inequality relative to the status quo because younger cohorts have longer remaining lifetimes and thus bear adjustment longer; however, failing to consolidate can raise interest rates, lower output, and reduce welfare—harming the young more.
- Example scenario (VAT hike):
  - Government proposal: increase VAT by “5 percentage points to 10 percent by FY2015.”
  - OLG simulation results:
    - The VAT hike would increase the PDV of the lifetime tax burden of those aged 70 years by “30 percent of current per household wage income before taxes.”
    - The VAT hike would raise the lifetime tax burden of those aged 20 years by “100 percent” (of current per household wage income before taxes).
- Broader projection context:
  - January 2012 Cabinet Office projections suggest that under prudent macroeconomic assumptions the government would need further expenditure cuts or a VAT beyond 10 percent, or both, to achieve its primary surplus goal—actions that would further increase intergenerational inequality.
- Comparative perspective:
  - Kotlikoff and Leibfritz (1999) comparison: once needed expenditure cuts or future tax increases are considered, Japan is characterized as “the most intergenerationally unequal economy in the world” in their analysis (Figure 2, right).

### Model specification and key numerical assumptions
- Model type and structure:
  - A standard lifecycle overlapping generations (OLG) model with perfect foresight and endogenous labor supply; no uncertainty about income or life length; no heterogeneity within each generation (one representative agent per generation).
  - Sectors: household, corporate, and government.
- Household sector:
  - Life span D = “60 years” (generations numbered 60), starting life at age 20 with zero assets and ending at age 79 without bequests.
  - Agents choose consumption and labor supply; those aged 65 years and older are eligible for public pension benefits.
- Corporate sector:
  - Production uses a Cobb–Douglas function with capital K, aggregate labor L, and labor productivity growth parameter λ; standard marginal conditions determine gross interest rate and wage rate.
- Government sector and fiscal rule:
  - Government revenue from personal income tax, social security contributions, and VAT; pay-as-you-go pension system with a fraction of pension benefits funded by tax revenue.
  - Nonpension social security spending and other government spending affect the fiscal balance but do not enter household utility.
  - Baseline structural primary balance path assumed: structural primary balance improves by “10 percentage points of GDP from –6.5 percent in year T – 1 to 3.5 percent in year T + 8.”
    - Note: “The current period is year T. If 2012 is considered to be year T, year T + 8 corresponds to 2020.”
  - All cyclical factors affecting the fiscal balance are set to zero so structural and primary balances coincide.
- Demographic assumption on generation size:
  - Growth rate of generation size for newborns set at “–0.75 percent” in the transition phase (between T – 10 and T + 59) and “0 percent” for newborns in year T + 60 and thereafter.

### Model limitations and interpretation caveats
- Simplifications that affect interpretation:
  - Nonpension social security benefits and other forms of government spending are treated as exogenous and do not affect household utility.
  - No uncertainty about pension benefits, wage income, or life length; no within-generation heterogeneity (single representative agent per generation).
  - The assumption of guaranteed future pension payments (no uncertainty about pensions) is important because it implies pensions will be paid fully irrespective of fiscal sustainability in the model.
- Implication:
  - Results should be read cautiously given these simplifications; they are informative about general-equilibrium and intergenerational allocation effects but abstract from uncertainty and intra-cohort distributional heterogeneity.

*Source: _wp12197 - References .........................................................................................................*

### 12.      What does the OLG simulation tell us about the intergenerational resource

### 12.      What does the OLG simulation tell us about the intergenerational resource implications of various fiscal adjustment measures?

### Key findings from the OLG simulation
- The simulation compares lifetime resource burdens (present discounted value, in percent of current per household before tax wage income) for five permanent measures, each improving the structural primary balance by 0.5 percent of GDP:
  1. Reducing the pension replacement ratio (while maintaining the pension eligibility age).
  2. Raising the pension eligibility age.
  3. Raising the pension contribution rate.
  4. Containing nonpension social security benefits.
  5. Raising the VAT rate.
- Implementation timing:
  - Each measure is implemented immediately in year T + 3, except measure (2) in which the pension eligibility age starts to rise gradually in T + 3.
- General equilibrium caveat:
  - The paper assumes fiscal consolidation does not change the security of future provision of government services and transfers (e.g., pension). If consolidation improved confidence and the perceived security of future benefits, the net burden could be smaller than reported.

### Comparative results on intergenerational burden and fairness
- Reducing the pension replacement ratio versus raising the pension eligibility age:
  - Reducing the replacement ratio (to achieve 0.5 percent of GDP savings) is modeled as:
    - Reduce the replacement ratio by about 5 percent in year T + 3 (i.e., reduce the replacement ratio to average wage income before taxes by about 2 percentage points from 40 percent to 38 percent).
    - The change affects immediately in year T + 3 all generations receiving pension benefits.
    - The paper clarifies this is not an across-the-board identical cut by income; it implicitly assumes a disproportionately larger pension benefit reduction for higher income households.
  - Raising eligibility age is modeled as:
    - Raise the eligibility age for the basic pension from 65 to 66 in year T + 3 and to 67 in T + 5 (while maintaining the private pension contribution rate).
  - Distributional implications:
    - Raising the eligibility age imposes a zero burden on generations already aged 65 years or older (because they already receive benefits).
    - Reducing the replacement ratio affects all generations receiving pensions, lowering the burden for younger generations given a fixed aggregate saving of 0.5 percentage point of GDP.
    - Bottom line: Reducing the replacement ratio (applied immediately to all beneficiaries) would be fairer in terms of intergenerational equality than increasing the eligibility age.
- Raising pension contribution rate or personal income tax:
  - These measures worsen existing intergenerational imbalance relative to reducing the replacement ratio.
  - For younger generations, lifetime burden increases much more with higher pension contributions (starting in year T + 3) because only working generations pay the higher contributions.
  - Similar qualitative effect for higher personal income tax, because it is proportional to income.
  - Aggregate consequences: Raising the pension contribution rate has greater distortionary impact on labor supply and capital accumulation, reducing output more than a VAT increase.
- Containing nonpension social security benefits:
  - Would increase the lifetime burden more equally across generations than reducing pension benefits or raising the pension contribution rate — a middle option between containing pension benefits and raising pension contributions.
  - Simulation assumes per household nonpension social security benefits for those aged 65 years or older are three times as high as those for the rest of the population; results are not very sensitive to this choice.
- Raising the VAT rate:
  - Intergenerational implication similar to containing nonpension social security benefits — raises the burden relatively equally across generations compared to lower pension benefits or higher pension contributions.
  - Macro effect: VAT increase dampens aggregate output, but less than an increase in the pension contribution rate because the latter more strongly reduces labor supply.
  - Nominal pension benefits linkage caveat:
    - In reality, a VAT increase would raise CPI prices and thus nominal pension benefits (to which benefits are linked), which would reduce the net burden by raising the replacement ratio, assuming wages do not rise as much as CPI prices.
    - For simplicity, the paper assumes a VAT increase does not change the replacement ratio — i.e., the VAT increase considered should be interpreted as a combination of a VAT increase and a reduction in the pace of pension benefit increases.
  - Behavioral note: More than half (about 60 percent) of consumption of those aged over 65 years is financed by past savings.

### Macroeconomic implications (select quantitative outcomes preserved as reported)
- Relative GDP and saving effects (OLG simulation deviations relative to raising the pension eligibility age, policy implementation in year T + 3):
  - Raising pension contribution rate versus raising VAT rate:
    - GDP level deviation (in percent of GDP) is depicted for years T+3 through T+6 showing a larger negative deviation for raising pension contribution rate than for raising VAT rate.
    - Saving rate deviation (in percentage points of GDP) is also more negative for raising pension contribution rate than for raising VAT rate in years T+3 through T+6.
- Empirical consistency:
  - Finding consistent with OECD evidence that growth is moderately, but negatively correlated with the burden from social security contributions and employee income tax.

### Assessment of consolidation packages (10 percentage points of GDP total structural adjustment)
- Two illustrative options for improving the structural primary balance by 10 percentage points of GDP between year T-1 and T+8:
  - Option (1): 1.5 percentage points of savings from social security benefits (0.5 in pension benefits and 1.0 in nonpension social security benefits) and 8.5 percentage points of revenue and nonsocial security adjustment.
    - Option (1a): Reducing the pension replacement ratio generates 0.5 percentage points of GDP savings from pension reform.
    - Option (1b): Raising the pension eligibility age generates 0.5 percentage points of GDP savings from pension reform.
  - Option (2): 10 percentage points of revenue and nonsocial security adjustment (no social security reforms).
- Distributional consequences under both options:
  - The increase in lifetime burden is overwhelmingly larger for young generations under both options.
  - Example: The PDV impact for those aged 20 years amounts to about 500 percent of current (year T) per household wage income before taxes (i.e., as large as 5 years of the current per household wage income).
  - Option (1) (with social security reforms) reduces the PDV net burden of those aged 20 years by about 15 percentage points of current per household wage income before taxes, relative to option (2).
  - Including a reduction in the pension replacement ratio (1a) increases the burden for current pensioners more and thus corrects intergenerational resource imbalance more than including an increase in the pension eligibility age (1b).
- Interpretation:
  - Given the substantial total burden for young generations, including social security spending reforms in a fiscal consolidation package — which work toward correcting intergenerational imbalance — would be appropriate, even if the benefit for the young may be modest at most.
  - However, relying excessively on social security spending reforms—particularly a reduction in the replacement ratio applied to all generations receiving pension benefits—could have serious welfare implications for seniors and greater negative effects on low-income retirees (risk of pushing low-income retirees below the relative poverty line). This argues for a balanced combination of social security spending reforms and revenue measures.
- Relative attractiveness of revenue measures:
  - Both higher pension contributions and a higher VAT would affect output and intergenerational equity, but the impact of a VAT increase would be less adverse than raising pension contributions.

### Summary assessment table (verbatim portrayal of qualitative judgments from the source)
- Intergenerational fairness / Aggregate economic impact:
  - 1) Reducing pension replacement ratio (while maintaining the pension eligibility age): ＋ (more intergenerationally fair)
  - 2) Raising pension eligibility age: (no symbol reported in text excerpt for fairness; presented as intermediate)
  - 3) Raising pension contribution rate/personal income tax rate: －－ (worse for intergenerational fairness and aggregate economy)
  - 4) Containing nonpension social security benefits: － (less negative than measure 3)
  - 5) Raising VAT rate: － (but less negative than measure 3)

*Source: IMF staff calculations as reported in the chapter "12. What does the OLG simulation tell us about the intergenerational resource implications of various fiscal adjustment measures?"*

### 15.      An adjustment of 10 percentage points would raise the overall lifetime net burden

### _wp12197 - 15.      An adjustment of 10 percentage points would raise the overall lifetime net burden

### Effects of a 10 percentage point adjustment combined with social security reforms
- The right-hand side of Figure 4 shows overall lifetime net burden combining: burden implied by policy as of 2003 and that from the 10 percentage point adjustment of GDP with social security spending reforms (year T (current year) is set at 2012).
- For those aged 20–29:
  - The total net PDV burden would amount to 1600 percent of current per household wage income before taxes.
  - This is nearly 40 percent higher than the net burden implied by the 2003 policy estimates without the 10 percentage point adjustment.
- For those aged 70 or higher:
  - The increase in the burden due to the adjustment would be minimal relative to the net benefits implied by the 2003 policy estimates.
- For those aged 60–69:
  - The net burden from fiscal consolidation would be larger, but the total net burden would remain negative.

### Timing of fiscal consolidation — scenarios and quantitative consequences
- Baseline OLG simulation assumption:
  - A 10 percentage point improvement in the structural primary balance between year T – 1 and T + 8, with consolidation starting gradually in year T.
- Delay scenario: start of adjustment delayed by 3 years to year T + 3 (and fiscal consolidation continues through T + 11).
- Two examined cases when delaying by 3 years:
  - Maintain the same size of fiscal adjustment (10 percentage points of GDP).
    - Lifetime burden would be smaller for all generations and the level of GDP would be higher initially relative to the no-delay scenario, due to lower (net tax) burden.
    - However, higher deficits would raise public debt and eventually crowd out output through higher interest rates (Figure 5, left).
    - Costs of crowding-out increase the longer the delay.
    - Note: results may underestimate crowding-out costs because they exclude nonlinear interest rate responses to debt once debt exceeds a certain threshold, even though net public debt reaches nearly 300 percent of GDP in year T + 60 (end-life of those aged 20 years in year T).
  - Avoid crowding-out by targeting the same debt-to-GDP level by year T + 60 as in the no-delay scenario.
    - Overall adjustment would need to be larger by about 1 percentage point of GDP.
    - Result: the increase in the PDV lifetime burden for those 20 years of age in year T would be larger by 20 percentage points of the current per household wage before taxes, assuming additional savings arise from nonsocial security spending (Figure 5, right).
    - The increase would be substantially smaller for senior generations relative to the no-delay scenario, exacerbating intergenerational resource imbalance.
- Conclusion from timing analysis:
  - The timing of fiscal consolidation is quantitatively as important as its composition.
  - Delaying fiscal consolidation could be costly and worsen intergenerational resource inequality.

### Political economy implications
- Delaying consolidation could lower the burden for older generations, creating political difficulty for early consolidation.
- Japan context:
  - Share of middle-aged and senior voters is relatively high because of declining birth rates and the baby boomer bulge.
  - Even with an eventually larger overall adjustment, older generations could benefit from a delay, making early implementation politically difficult.
- Proposal:
  - An independent body aimed at ensuring fair intergenerational resource distribution has been proposed by some, but establishing such an institution remains politically challenging.

### Policy options to correct intergenerational resource imbalance
- Allow greater immigration:
  - Paper assumes size of a generation that joins the population declines by 0.75 percent every year between year T – 10 and T + 60.
  - OLG simulation indicates: if immigration keeps the size of a newly-joining generation constant next year (year T + 1) and after, the per household lifetime burden of those currently aged 20 (in year T) for financing senior generations’ pension benefits would decline by 20 percentage points of current per household wage income (before taxes) relative to a no-immigration case.
  - This estimate is based on fiscal consolidation of 10 percentage points of GDP between year T – 1 and T + 8.
  - Note on magnitude: with this parameter, share of immigrants rises by 6 percentage points by year T + 30 and by 25 percentage points by year T + 60; share of immigrants in total population in Japan was about 2 percent in 2009.
  - Greater immigration could reduce the debt-to-GDP ratio faster by boosting labor supply and level of GDP, reducing young generations’ burden further by lowering needed fiscal adjustment.
- Raise productivity growth through structural reforms:
  - Higher productivity growth trims needed size of fiscal adjustment (given a debt-to-GDP target), reducing young generations’ burden and helping correct intergenerational imbalance.
- Expand transfers to young generations (public education spending and child allowances):
  - Would help mitigate intergenerational imbalances directly and indirectly (raising fertility rates and labor input over time).
  - Japan’s public education and family spending is the lowest among OECD economies (chart referenced).
  - Fiscal space for such policies may be limited; higher spending requires savings in other areas.
  - To correct intergenerational inequality, Japan would need to reduce expenditure for senior generations or collect more revenue from them.
  - Raising the inheritance tax rate could be an option to secure revenue for financing larger education and family spending.
- Other design considerations:
  - If additional savings arise from nonsocial security spending, impacts on lifetime burden could be concentrated on younger cohorts (see timing scenario above).

### Other issues in implementing social security spending reforms
- Poverty risks:
  - Fiscal consolidation would substantially raise the burden for young generations and, combined with social security spending reforms, could hit older generations who began retirement without enough savings.
  - Fiscal consolidation risks increasing incidence of poverty among both young and old generations, particularly if accompanied by an across-the-board pension replacement cut.
  - To address poverty risk, policymakers could:
    - Consider strengthening targeted income transfers; and
    - Exclude households with low income and wealth from reductions in social security benefits.
  - Both measures require means testing; introduction of a tax identification system is desirable.
- Labor market interactions:
  - Concern exists that increased old-age labor participation (driven by lower pension benefits) might crowd out youth employment.
  - International evidence does not support crowding-out: Gruber, Milligan, and Wise (2009) reported youth employment is positively correlated with old-age employment, controlling for macro shocks.
  - OLG simulation finding: given a fixed size of fiscal consolidation including social security reforms (especially curbing pension benefits), such reforms would be relatively beneficial for young generations; lower pension benefits may encourage old-age labor participation and could have a positive impact on aggregate growth.

### Conclusions and cross-country relevance
- A balanced fiscal consolidation that includes both social security spending reforms and revenue measures would be the fairest approach to addressing intergenerational inequality.
- OLG simulations show social security reforms, in particular reducing pension benefits (e.g., by raising the pension eligibility age), would have a less deleterious effect on intergenerational inequality than some alternative measures.
- Combining social security spending reforms with revenue measures could produce a balanced fiscal consolidation.
- Delaying fiscal consolidation could further worsen the imbalance in intergenerational resources.
- Findings may be relevant for other economies:
  - Intergenerational resource imbalance is not unique to Japan; demographic aging and revenue shortfalls relative to rising social security spending can worsen the imbalance.
  - Japan’s experience could provide lessons for other aging economies, including in Asia.

### Box 1 — Public Pension System in Japan (key facts)
- Structure:
  - Two-layer system.
  - First layer: basic pension, providing flat-rate pension benefits (currently ¥66,000 per month).
    - As of 2012, those aged 65 or higher who have paid contributions for 25 years or longer are eligible for the basic pension.
    - Contribution to the first layer is mandatory for all residents in Japan aged between 20 and 59.
    - Those not eligible for the basic pension may receive separate public assistance if their income and wealth are below certain levels.
  - Second layer: defined-benefit pension system.
    - Pension contribution and benefits are proportional to income levels during the contribution period.
    - Private company and government employees participate in the second layer (the second tier for self-employed people, participation in which is voluntary, also exists).
    - The male eligibility age for the second tier pension will be gradually raised to 65 by 2025 from the current age of 60.
- Replacement ratios and fiscal size:
  - According to the OECD (2011), the replacement ratio for those currently at age 20 with average earnings will be about 0.4, lower than the OECD average of 0.5.
  - Note: OECD’s estimates do not reflect replacement ratio for current pensioners, which in Japan is higher than the future replacement ratio for those currently at age 20.
- FY2009 (April 2009 - March 2010) figures:
  - Aggregate public pension benefits amounted to nearly ¥50 trillion (10 percent of GDP).
  - The government contributed ¥10 trillion to the public pension, which financed 50 percent of ¥20 trillion of basic pension benefits (first layer).
  - Aggregate pension benefits breakdown (as of FY2009):
    - Second layer: Y28 trillion (6% of GDP)
    - First layer: Basic pension Y20 trillion (4% of GDP)

*Sources: Japanese government and staff calculation.*

### Appendix I. Parameter Values and Key Simulation Assumptions

### Appendix I. Parameter Values and Key Simulation Assumptions

### Model parameter values and sensitivity to parameter choices
- Key calibrated parameters:
  - ρ (Elasticity of substitution between consumption and leisure) = 0.8
  - γ (Intertemporal elasticity of substitution) = 0.75
  - θ (Weight to utility from leisure) = 0.5
  - β (Time discount factor) = 0.9995
  - Age profile of labor efficiency = Estimated from semi aggregate data
  - Growth rate of population size in the transition phase = -0.0075
  - α (Capital share) = 0.3
  - λ (Annual growth rate of labor productivity) = 0.014
  - δ (Annual depreciation rate) = 0.05
  - C-efficiency ratio: VAT revenue/(total consumption*VAT rate) = 0.7
  - Initial VAT rate = 0.1
  - Initial pension contribution rate + personal income tax rate = 0.2
  - Pension replacement ratio (to before tax average wage income) = 0.4
  - Share of basic pension benefits in total pension benefits = 0.4
  - Share of public debt crowding out private capital = 0.2

- Parameter provenance and calibration notes:
  - ρ and γ are from Miles (1999). β is set at 0.9995 and is higher than standard values; a high β is necessary to replicate low interest rates under high public debt levels (as currently in Japan).
  - Changing these parameters jointly alters the size of the overall household burden from fiscal consolidation but does not change the key messages in the main text.
  - Example sensitivity: using Uemura (2004)’s parameter values (ρ, γ, θ) = (0.6, 0.5, 0.1), option (1a), which includes social security reforms, would still reduce the PDV burden of those at age 20 by about 15 percentage points of current per household before tax wage income, relative to option (2) with no social security reforms (detailed results not reported here).

- Age profile of labor efficiency estimation:
  - Log(labor efficiency) = 0.97101 + 0.048505*(age-20) -0.000915*(age-20)^2 (parameters estimated using Basic Survey on Wage Structure (2005)). After calculating this equation, the average of labor efficiency (in level, not in log) is normalized at 1.

- Notes on productivity and VAT:
  - λ = 0.014 corresponds to total factor productivity growth of 0.01 (1 percent).
  - While Japan’s narrowly defined VAT rate is 0.05 (5 percent), the simulation uses an initial VAT rate of 0.1 to capture other consumption taxation.
  - Pension replacement ratio: 0.4 times before tax wage income is about 0.5 times after tax wage income.

### Population growth assumptions and sensitivity
- Baseline growth rate of generation size:
  - Set at –0.75 percent for newborns in the transition phase (between T – 10 and T + 59) and 0 percent for newborns in year T + 60 and after.
  - This approximates overall population growth in the near to medium term but may be optimistic in the long term (pace of decline may be too slow).

- Sensitivity results:
  - Lowering the growth rate of generation size to –1 percent from the baseline value of –0.75 percent would raise the lifetime burden for those 20 years of age in year T by 15 percentage points of current per household wage income before taxes.
  - A more rapid population shrinkage increases pension benefits (in percent of GDP) and therefore requires larger spending adjustments elsewhere to achieve the same primary balance path; this results in a larger burden for young generations.
  - Including social security reform in a fiscal consolidation package would still reduce the burden for young generations despite faster population shrinkage.

### Baseline fiscal-path and simulation assumptions
- Structural (cyclically adjusted) primary balance path (option (1a), baseline 10 percentage point adjustment):
  - The structural primary balance improves from –6.5 percent of GDP in year T – 1 (2011) to 3.5 percent of GDP in year T + 8 (2020).
  - The structural primary balance stays at 3.5 percent of GDP through year T + 99 (2111).
  - The structural primary balance adjusts in year T + 100 (2112) and after so that the net public debt to GDP ratio remains constant.
  - Size of total (structural) adjustment assumed to be 10 percentage points of GDP between year T-1 and year T+8.

- Determination of other spending and revenues:
  - Nonpension social security spending and other government spending are determined as residuals given the path of the structural primary balance, revenue, and pension spending.

- Perfect foresight assumption and robustness:
  - Simulations assume perfect foresight: households expect the exact path of future fiscal consolidation rationally.
  - This assumption may be restrictive; an alternative where households expected a more gradual consolidation through year T – 1 and then realized in T – 1 that the actual faster path would occur changes results little.
  - Illustration: option (1a) under perfect foresight versus option (1a) with change in expectations (households had expected a more gradual adjustment of 10 percentage points between year T-1 and T+11 and realized in year T-1 that the actual adjustment would take place between year T-1 and T+8) shows limited differences in OLG simulation results for increase in total lifetime burden (present discounted value, in percent of current (year T) per household before tax wage income).

### Key quantitative points and scenario specifications
- Baseline parameter values (Table A) reproduced exactly:
  - Elasticity of substitution between consumption and leisure (ρ) = 0.8
  - Intertemporal elasticity of substitution (γ) = 0.75
  - Weight to utility from leisure (θ) = 0.5
  - Time discount factor (β) = 0.9995
  - Age profile of labor efficiency = Estimated from semi aggregate data
  - Growth rate of population size in the transition phase = -0.0075
  - Capital share (α) = 0.3
  - Annual growth rate of labor productivity (λ) = 0.014
  - Annual depreciation rate (δ) = 0.05
  - C-efficiency ratio: VAT revenue/(total consumption*VAT rate) = 0.7
  - Initial VAT rate = 0.1
  - Initial pension contribution rate + personal income tax rate = 0.2
  - Pension replacement ratio (to before tax average wage income) = 0.4
  - Share of basic pension benefits in total pension benefits = 0.4
  - Share of public debt crowding out private capital = 0.2

- Fiscal outcome targets and calibration:
  - Net public debt to GDP ratio is calibrated to broadly replicate historical data through T – 2 (2010).
  - Option (1a) path is the baseline for structural primary balance and net public debt simulations.

*Source: Appendix I. Parameter Values and Key Simulation Assumptions (content unit)._wp12197 - Appendix I. Parameter Values and Key Simulation Assumptions*

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