We study interactions between progressive labor taxation and social security reform. Increasing longevity puts fiscal strain that necessitates social security reform. The current social security is redistributive, thus providing (at least partial) insurance against idiosyncratic income shocks, but at the expense of labor supply distortions. A reform that links pensions to individual incomes reduces distortions associated with social security contributions but incurs insurance loss. We show that the progressive labor tax can partially substitute for the redistribution in social security, thus reducing the insurance loss.
Progressing towards efficiency: the role for labor tax progression in reforming social security
1. Progressing into efficiency:
the role for labor tax progression in privatizing social security
Oliwia Komada (FAME|GRAPE)
Krzysztof Makarski (FAME|GRAPE and Warsaw School of Economics)
Joanna Tyrowicz (FAME|GRAPE, University of Regensburg, and IZA)
EPCS, Hannover, 2023
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3. Motivation
Social security is essentially about insurance:
• old age (between cohorts) & mortality (annuitized)
Benartzi et al. 2011, Bruce & Turnovsky 2013, Reichling & Smetters 2015, Caliendo et al. 2017
• low income (within cohort redistribution)
Cooley & Soares 1996, Tabellini 2000
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4. Motivation
Social security is essentially about insurance:
• old age (between cohorts) & mortality (annuitized)
Benartzi et al. 2011, Bruce & Turnovsky 2013, Reichling & Smetters 2015, Caliendo et al. 2017
• low income (within cohort redistribution)
Cooley & Soares 1996, Tabellini 2000
Prevailing consensus:
• privatization of social security brings efficiency gains,
• but reduces (within cohort) redistribution
• this insurance loss reduces overall welfare effect of such reforms
e.g. Nishiyama & Smetters (2007)
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5. Motivation
Social security is essentially about insurance:
• old age (between cohorts) & mortality (annuitized)
Benartzi et al. 2011, Bruce & Turnovsky 2013, Reichling & Smetters 2015, Caliendo et al. 2017
• low income (within cohort redistribution)
Cooley & Soares 1996, Tabellini 2000
Prevailing consensus:
• privatization of social security brings efficiency gains,
• but reduces (within cohort) redistribution
• this insurance loss reduces overall welfare effect of such reforms
e.g. Nishiyama & Smetters (2007)
Our approach: replace redistribution in social security with tax progression
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6. Motivation
Social security is essentially about insurance:
• old age (between cohorts) & mortality (annuitized)
Benartzi et al. 2011, Bruce & Turnovsky 2013, Reichling & Smetters 2015, Caliendo et al. 2017
• low income (within cohort redistribution)
Cooley & Soares 1996, Tabellini 2000
Prevailing consensus:
• privatization of social security brings efficiency gains,
• but reduces (within cohort) redistribution
• this insurance loss reduces overall welfare effect of such reforms
e.g. Nishiyama & Smetters (2007)
Our approach: replace redistribution in social security with tax progression
Bottom line: shift insurance from retirement to working period →
improve efficiency of social security → raise welfare.
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28. Redistribution through social security
Denote: PV Pen
t (θ) =
b2,t+1(θ)
1 + r
− τwt ωθℓ1,t (θ), then:
θH gains from less redistribution in social security
∆PV Pen
t (θH ) = PV Pen,BIS
t (θH ) − PV Pen,BEV
t (θH ) =
τwt
2
(ωH ℓBIS
(θH ) − ωLℓBEV
1 (θL)
| {z }
redistribution effect>0
]
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29. Redistribution through social security
Denote: PV Pen
t (θ) =
b2,t+1(θ)
1 + r
− τwt ωθℓ1,t (θ), then:
θH gains from less redistribution in social security
∆PV Pen
t (θH ) = PV Pen,BIS
t (θH ) − PV Pen,BEV
t (θH ) =
τwt
2
(ωH ℓBIS
(θH ) − ωLℓBEV
1 (θL)
| {z }
redistribution effect>0
]
θL loses from less redistribution in social security
∆PV Pen
t (θL) = PV Pen,BIS
t (θL) − PV Pen,BEV
t (θL) =
τwt
2
(ωLℓBEV
1 (θL) − ωH ℓBIS
(θH )
| {z }
redistribution effect<0
]
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30. Redistribution through social security
Denote: PV Pen
t (θ) =
b2,t+1(θ)
1 + r
− τwt ωθℓ1,t (θ), then:
θH gains from less redistribution in social security
∆PV Pen
t (θH ) = PV Pen,BIS
t (θH ) − PV Pen,BEV
t (θH ) =
τwt
2
(ωH ℓBIS
(θH ) − ωLℓBEV
1 (θL)
| {z }
redistribution effect>0
]
θL loses from less redistribution in social security
∆PV Pen
t (θL) = PV Pen,BIS
t (θL) − PV Pen,BEV
t (θL) =
τwt
2
(ωLℓBEV
1 (θL) − ωH ℓBIS
(θH )
| {z }
redistribution effect<0
]
social security redistribution effect −→ benefits θH , harms: θL,
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31. Redistribution through social security
Denote: PV Pen
t (θ) =
b2,t+1(θ)
1 + r
− τwt ωθℓ1,t (θ), then:
θH gains from less redistribution in social security
∆PV Pen
t (θH ) = PV Pen,BIS
t (θH ) − PV Pen,BEV
t (θH ) =
τwt
2
(ωH ℓBIS
(θH ) − ωLℓBEV
1 (θL)
| {z }
redistribution effect>0
]
θL loses from less redistribution in social security
∆PV Pen
t (θL) = PV Pen,BIS
t (θL) − PV Pen,BEV
t (θL) =
τwt
2
(ωLℓBEV
1 (θL) − ωH ℓBIS
(θH )
| {z }
redistribution effect<0
]
social security redistribution effect −→ benefits θH , harms: θL, can θL be compensated through taxes?
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32. Redistribution through tax system
1. % ∆ in labor supply is equal for both productivity types and increases with η
ℓBIS
(θ) − ℓBEV
(θ)
ℓBEV (θ)
=
(1 − τℓ(1 − τ))
(1 − τ − τℓ(1 − τ))
η
− 1 ≡ ξη
− 1
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33. Redistribution through tax system
1. % ∆ in labor supply is equal for both productivity types and increases with η
ℓBIS
(θ) − ℓBEV
(θ)
ℓBEV (θ)
=
(1 − τℓ(1 − τ))
(1 − τ − τℓ(1 − τ))
η
− 1 ≡ ξη
− 1
2. % ∆ in government revenue increases with η (Frisch elasticity) ⇒ pool for µt ↑
RBIS
− RBEV
RBEV
≡ ξη
− 1
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34. Redistribution through tax system
1. % ∆ in labor supply is equal for both productivity types and increases with η
ℓBIS
(θ) − ℓBEV
(θ)
ℓBEV (θ)
=
(1 − τℓ(1 − τ))
(1 − τ − τℓ(1 − τ))
η
− 1 ≡ ξη
− 1
2. % ∆ in government revenue increases with η (Frisch elasticity) ⇒ pool for µt ↑
RBIS
− RBEV
RBEV
≡ ξη
− 1
3. The change in net tax transfer for θL positive and for θH negative
∆µt − τℓ(1 − τ)ωLwt ∆ℓt (θL) 0 and ∆µt − τℓ(1 − τ)ωH wt ∆ℓt (θH ) 0
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35. Redistribution through tax system
1. % ∆ in labor supply is equal for both productivity types and increases with η
ℓBIS
(θ) − ℓBEV
(θ)
ℓBEV (θ)
=
(1 − τℓ(1 − τ))
(1 − τ − τℓ(1 − τ))
η
− 1 ≡ ξη
− 1
2. % ∆ in government revenue increases with η (Frisch elasticity) ⇒ pool for µt ↑
RBIS
− RBEV
RBEV
≡ ξη
− 1
3. The change in net tax transfer for θL positive and for θH negative
∆µt − τℓ(1 − τ)ωLwt ∆ℓt (θL) 0 and ∆µt − τℓ(1 − τ)ωH wt ∆ℓt (θH ) 0
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36. Redistribution through tax system
1. % ∆ in labor supply is equal for both productivity types and increases with η
ℓBIS
(θ) − ℓBEV
(θ)
ℓBEV (θ)
=
(1 − τℓ(1 − τ))
(1 − τ − τℓ(1 − τ))
η
− 1 ≡ ξη
− 1
2. % ∆ in government revenue increases with η (Frisch elasticity) ⇒ pool for µt ↑
RBIS
− RBEV
RBEV
≡ ξη
− 1
3. The change in net tax transfer for θL positive and for θH negative
∆µt − τℓ(1 − τ)ωLwt ∆ℓt (θL) 0 and ∆µt − τℓ(1 − τ)ωH wt ∆ℓt (θH ) 0
Reform + lump sum transfers bundle =⇒ positive (increasing in η) transfers from θH -type households to
the θL-type households through the tax system.
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37. Redistribution through tax system
1. % ∆ in labor supply is equal for both productivity types and increases with η
ℓBIS
(θ) − ℓBEV
(θ)
ℓBEV (θ)
=
(1 − τℓ(1 − τ))
(1 − τ − τℓ(1 − τ))
η
− 1 ≡ ξη
− 1
2. % ∆ in government revenue increases with η (Frisch elasticity) ⇒ pool for µt ↑
RBIS
− RBEV
RBEV
≡ ξη
− 1
3. The change in net tax transfer for θL positive and for θH negative
∆µt − τℓ(1 − τ)ωLwt ∆ℓt (θL) 0 and ∆µt − τℓ(1 − τ)ωH wt ∆ℓt (θH ) 0
Reform + lump sum transfers bundle =⇒ positive (increasing in η) transfers from θH -type households to
the θL-type households through the tax system.
Tax system redistribution effect −→ benefits θL at the expense of θH ,
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38. Redistribution through tax system
1. % ∆ in labor supply is equal for both productivity types and increases with η
ℓBIS
(θ) − ℓBEV
(θ)
ℓBEV (θ)
=
(1 − τℓ(1 − τ))
(1 − τ − τℓ(1 − τ))
η
− 1 ≡ ξη
− 1
2. % ∆ in government revenue increases with η (Frisch elasticity) ⇒ pool for µt ↑
RBIS
− RBEV
RBEV
≡ ξη
− 1
3. The change in net tax transfer for θL positive and for θH negative
∆µt − τℓ(1 − τ)ωLwt ∆ℓt (θL) 0 and ∆µt − τℓ(1 − τ)ωH wt ∆ℓt (θH ) 0
Reform + lump sum transfers bundle =⇒ positive (increasing in η) transfers from θH -type households to
the θL-type households through the tax system.
Tax system redistribution effect −→ benefits θL at the expense of θH , can it fully compensate θL for
the loss of redistribution in social security?
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39. Key results: Reform social security and extra government revenue → lump-sum grants µ
1 θH under BIS work more, have strictly higher pension benefits and pay higher taxes
(efficiency ↑ social security benefits ↑ tax liability ↑)
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40. Key results: Reform social security and extra government revenue → lump-sum grants µ
1 θH under BIS work more, have strictly higher pension benefits and pay higher taxes
(efficiency ↑ social security benefits ↑ tax liability ↑)
2 θL under BIS work more, have (most likely) lower pension benefits and pay lower taxes
(efficiency ↑ social security benefits ↓ tax liability ↓)
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41. Key results: Reform social security and extra government revenue → lump-sum grants µ
1 θH under BIS work more, have strictly higher pension benefits and pay higher taxes
(efficiency ↑ social security benefits ↑ tax liability ↑)
2 θL under BIS work more, have (most likely) lower pension benefits and pay lower taxes
(efficiency ↑ social security benefits ↓ tax liability ↓)
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42. Key results: Reform social security and extra government revenue → lump-sum grants µ
1 θH under BIS work more, have strictly higher pension benefits and pay higher taxes
(efficiency ↑ social security benefits ↑ tax liability ↑)
2 θL under BIS work more, have (most likely) lower pension benefits and pay lower taxes
(efficiency ↑ social security benefits ↓ tax liability ↓)
3 ∃ η̃ s.t. for θL HHs redistribution lost in pension system is fully compensated by tax system
∆PV Pen
(θL) = ∆Tax(θL)
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43. Key results: Reform social security and extra government revenue → lump-sum grants µ
1 θH under BIS work more, have strictly higher pension benefits and pay higher taxes
(efficiency ↑ social security benefits ↑ tax liability ↑)
2 θL under BIS work more, have (most likely) lower pension benefits and pay lower taxes
(efficiency ↑ social security benefits ↓ tax liability ↓)
3 ∃ η̃ s.t. for θL HHs redistribution lost in pension system is fully compensated by tax system
∆PV Pen
(θL) = ∆Tax(θL)
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44. Key results: Reform social security and extra government revenue → lump-sum grants µ
1 θH under BIS work more, have strictly higher pension benefits and pay higher taxes
(efficiency ↑ social security benefits ↑ tax liability ↑)
2 θL under BIS work more, have (most likely) lower pension benefits and pay lower taxes
(efficiency ↑ social security benefits ↓ tax liability ↓)
3 ∃ η̃ s.t. for θL HHs redistribution lost in pension system is fully compensated by tax system
∆PV Pen
(θL) = ∆Tax(θL)
4 ∃ η ∈ (0, η̃) s.t. for η η reform with µ is a Pareto-improving (by continuity of the utility function)
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45. Key results: Reform social security and extra government revenue → lump-sum grants µ
1 θH under BIS work more, have strictly higher pension benefits and pay higher taxes
(efficiency ↑ social security benefits ↑ tax liability ↑)
2 θL under BIS work more, have (most likely) lower pension benefits and pay lower taxes
(efficiency ↑ social security benefits ↓ tax liability ↓)
3 ∃ η̃ s.t. for θL HHs redistribution lost in pension system is fully compensated by tax system
∆PV Pen
(θL) = ∆Tax(θL)
4 ∃ η ∈ (0, η̃) s.t. for η η reform with µ is a Pareto-improving (by continuity of the utility function)
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46. Key results: Reform social security and extra government revenue → lump-sum grants µ
1 θH under BIS work more, have strictly higher pension benefits and pay higher taxes
(efficiency ↑ social security benefits ↑ tax liability ↑)
2 θL under BIS work more, have (most likely) lower pension benefits and pay lower taxes
(efficiency ↑ social security benefits ↓ tax liability ↓)
3 ∃ η̃ s.t. for θL HHs redistribution lost in pension system is fully compensated by tax system
∆PV Pen
(θL) = ∆Tax(θL)
4 ∃ η ∈ (0, η̃) s.t. for η η reform with µ is a Pareto-improving (by continuity of the utility function)
5 ∃ η ∈ (0, η) s.t. for η η reform with µ is a Hicks-improving (by the same token)
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48. Quantitative model
Consumers
• uncertain lifetimes: live for 16 periods, with survival πj 1
• ex ante heterogeneous productivity + uninsurable productivity risk
• consume, work and save based on CRRA instantaneous utility function 1
1−σ
c1−σ
− ϕ
1+1/η
ℓ1+1/η
• pay taxes (progressive on labor, linear on consumption and capital gains)
• contribute to social security, face natural borrowing constraint
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49. Quantitative model
Consumers
• uncertain lifetimes: live for 16 periods, with survival πj 1
• ex ante heterogeneous productivity + uninsurable productivity risk
• consume, work and save based on CRRA instantaneous utility function 1
1−σ
c1−σ
− ϕ
1+1/η
ℓ1+1/η
• pay taxes (progressive on labor, linear on consumption and capital gains)
• contribute to social security, face natural borrowing constraint
Firms and markets
• Cobb-Douglas production function, capital depreciates at rate d
• no annuity, financial markets with (risk free) interest rate
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50. Quantitative model
Government
• Finances government spending Gt , constant between scenarios,
• Balances pension system: subsidyt
• Services debt: rt Dt ,
• Collects taxes on capital, consumption, labor, and covers lump-sum grant
(progressive labor tax given by Benabou form)
Gt + subsidyt + rt Dt + Mt = τk,t rt At + τc,t Ct + Taxℓ,t + ∆Dt
where ∆Dt = Dt − Dt−1
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51. Policy experiment: comparative statics
Status quo: current US social security
• benefits redistributive, with high replacement rate for low income individuals
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52. Policy experiment: comparative statics
Status quo: current US social security
• benefits redistributive, with high replacement rate for low income individuals
• distortion: no individual link between labor supply and pension benefits
aj+1,t+1 + (1 + τc,t )cj,t = (1 + (1 − τk )rt )aj,t + (1 − τ)yj,t − Tt ((1 − τ)yj,t ) + Γj,t + 0 · τwt ωj,t ℓj,t + 0
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53. Policy experiment: comparative statics
Status quo: current US social security
• benefits redistributive, with high replacement rate for low income individuals
• distortion: no individual link between labor supply and pension benefits
aj+1,t+1 + (1 + τc,t )cj,t = (1 + (1 − τk )rt )aj,t + (1 − τ)yj,t − Tt ((1 − τ)yj,t ) + Γj,t + 0 · τwt ωj,t ℓj,t + 0
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54. Policy experiment: comparative statics
Status quo: current US social security
• benefits redistributive, with high replacement rate for low income individuals
• distortion: no individual link between labor supply and pension benefits
aj+1,t+1 + (1 + τc,t )cj,t = (1 + (1 − τk )rt )aj,t + (1 − τ)yj,t − Tt ((1 − τ)yj,t ) + Γj,t + 0 · τwt ωj,t ℓj,t + 0
Alternative: fully individualized social security and lump-sum grants
• benefits proportional to contribution, no redistribution through social security
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55. Policy experiment: comparative statics
Status quo: current US social security
• benefits redistributive, with high replacement rate for low income individuals
• distortion: no individual link between labor supply and pension benefits
aj+1,t+1 + (1 + τc,t )cj,t = (1 + (1 − τk )rt )aj,t + (1 − τ)yj,t − Tt ((1 − τ)yj,t ) + Γj,t + 0 · τwt ωj,t ℓj,t + 0
Alternative: fully individualized social security and lump-sum grants
• benefits proportional to contribution, no redistribution through social security
• no distortion: direct individual link between labor supply and pension benefits
aj+1,t+1 + (1 + τc,t )cj,t = (1 + (1 − τk )rt )aj,t + (1 − τ)yj,t − Tt ((1 − τ)yj,t ) + Γj,t + υR
j,t · τwt ωj,t ℓj,t + µt ,
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56. Policy experiment: comparative statics
Status quo: current US social security
• benefits redistributive, with high replacement rate for low income individuals
• distortion: no individual link between labor supply and pension benefits
aj+1,t+1 + (1 + τc,t )cj,t = (1 + (1 − τk )rt )aj,t + (1 − τ)yj,t − Tt ((1 − τ)yj,t ) + Γj,t + 0 · τwt ωj,t ℓj,t + 0
Alternative: fully individualized social security and lump-sum grants
• benefits proportional to contribution, no redistribution through social security
• no distortion: direct individual link between labor supply and pension benefits
aj+1,t+1 + (1 + τc,t )cj,t = (1 + (1 − τk )rt )aj,t + (1 − τ)yj,t − Tt ((1 − τ)yj,t ) + Γj,t + υR
j,t · τwt ωj,t ℓj,t + µt ,
• additional tax revenue (from increased efficiency) goes into lump-sum grants
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57. Calibration to replicate US economy (2015)
Preferences: instantaneous utility function take CRRA form with
• Risk aversion σ is equal to 2
• Disutility form work ϕ matches average hours 33%
• Frisch elasticity η is equal to 0.8
• Discounting rate δ matches interest K/Y ratio 2.9
Productivity risk and age profiles shock based on Borella et. al (2018):
Pension system
• Replacement rate ρ matches benefits as % of GDP 5.0%
• Contribution rate balances pension system in the initial steady state
• Pension eligibility age at 65
Taxes {τc , τk , τℓ} match revenue as % of GDP {2.8%, 5.4%, 9.2%}
Depreciation rate d based on Kehoe Ruhl (2010) equal to 0.06
Population survival probabilities based on UN forecast
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62. Labor supply reaction for η = 0.8
Average ∆ℓ ↑ 2.6% for HHs below median and 3.0% above median
Heathcote et al. (2008) argue for ↑ for high-productivity and ↓ for low-productivity.
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64. Distribution of welfare effects for η = 0.8
Under the veil of ignorance consumption equivalent increases by 0.3%
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65. Distribution of welfare effects for η = 0.8
Under the veil of ignorance consumption equivalent increases by 0.3%
Ex post almost universal gains (90%).
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72. Conclusions
1. Progression in the tax system can effectively substitute for progression in social security ...
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73. Conclusions
1. Progression in the tax system can effectively substitute for progression in social security ...
2. ... generating welfare gains
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74. Conclusions
1. Progression in the tax system can effectively substitute for progression in social security ...
2. ... generating welfare gains
3. With rising longevity, the potential welfare gains are higher.
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75. Conclusions
1. Progression in the tax system can effectively substitute for progression in social security ...
2. ... generating welfare gains
3. With rising longevity, the potential welfare gains are higher.
4. Important role for response of labor to the features of the pension system
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