人口老龄化、养老金与国际资本流动： 影响机制与实证研究*

本文详细梳理了人口老龄化对国际资本流动的影响机制，并利用1993-2012年98个国家或地区的面板数据实证分析其相关关系，同时验证了以养老金为中介变量的影响机制。研究发现：人口老龄化主要通过资本-劳动比率和经常账户余额影响国际资本流动；不管是中高收入和中低收入国家，人口老龄化程度越高，资本越倾向流出；随着实行现收现付（PAYG）养老制度国家的深入改革，作为资金池的养老金规模逐渐扩大，其对外投资活动也越活跃。     

Intergenerational consequences of gradual pension reforms

Balancing the government budget in an aging economy may require adjusting gradually pension benefits. Such policy change can take two forms: adjusting the accrual rate (the rate at which individuals built-up pension entitlements while working) or the indexation rate (the rate a which accrued entitlements are linked to nominal wage growth). We compare the consequences of such gradual policies across cohorts. We identify a fundamental generational trade-off between democracy and equality. In particular, we show that for Belgium, 80% of the population alive at the time of the reform prefers the accrual to the indexation reform, with the implication that the youngest half of the population would bear 85% of the total adjustment cost. The indexation reform provides more generational equality because the phasing in over time has larger base and thus benefit cut can be smaller per capita. We then consider other reforms improving the generational equality, showing that all those reforms fail to gain majority support. Finally, considering labor incentives, we show that the indexation reform is also more efficient than the accrual reform. Efficiency meets generational equality.     

When do we Start? Pension reform in ageing Japan

Japan is faced with rapid demographic ageing and fiscal challenges. This paper simulates pension reform to reduce the replacement rate by 20% and raise the retirement age by 3 years gradually over a 30‐year period. We consider three scenarios with different points in time to initiate reform in 2020, 2030 and 2040, respectively. A delay would suppress economic activities, lowering output by up to 4% and raising tax burden by more than 8% of total consumption. Delaying reform implies a transfer of costs of demographic ageing to the young and deteriorates the welfare of future generations by up to 3% in terms of consumption equivalence.     

Aging,Savings, and Public Pensions in Japan*

We analyze the impact of population aging on Japan's household savings rate and on its public pension system and the impact of that system on Japan's household savings rate and obtain the following results: first, the age structure of Japan's population can explain the level of, and past and future trends in, its household savings rate; second, the rapid aging of Japan's population is causing Japan's household savings rate to decline and this decline can be expected to continue; third, the pay‐as‐you‐go nature of the public pension system, combined with rapid population aging, created considerable intergenerational inequities and increased the savings rates of cohorts born after 1965, which in turn slowed the decline in Japan's household savings rate; and fourth, the 2004 public pension reform alleviated the intergenerational inequities of Japan's public pension system somewhat but will in the long run exacerbate the downward trend in Japan's household savings rate.     

Does Population Aging Hinder the Accumulation of Human Capital? Evidence from China

There is no consensus on the impact of population aging on education investment. To explore this question, we first build an overlapping generations (OLG) model to theoretically analyze the effect of population aging on human capital investment in China, and then test our theory by conducting an empirical study based on micro household data. We find the following. (1) Theoretically, the OLG model shows that population aging has a crowding-out effect on education investment. (2) Empirically, the results show that the share of education and training expenditures decreases by 5.27 percentage points as the ratio of old people in the household increases by 100 percentage points, which confirms the crowding-out effect of population aging on human capital investment. (3) The crowding-out effect is far more intense on urban households than on rural households since health care expenditures will be greater in urban areas as population aging increases. (4) A quantile regression indicates that the negative effect of population aging on the share of educational expenditure is concentrated in households with higher shares of education expenditures. We confirm the robustness of our results using regional fixed effect and instrumental variable (IV) regressions.     

Welfare Analysis of Pension Reforms in an Ageing Japan

This paper uses a computable general equilibrium model with overlapping generations to explore the effects of different public pension schemes on economic welfare, and intergenerational and intragenerational equity. Besides the benchmark case based on the 2004 public pension reform, the present paper considers two alternative reforms: financing the basic pension benefit through a consumption tax, and eliminating the earnings‐related pension benefit. The simulation results suggest that even the consumption‐tax financing of only the basic pension, namely, the combination of both reforms, might not improve overall economic welfare, although it increases economic output by inducing capital formation.     

Rates of Return and Early Retirement Disincentives: Evidence from a German Pension Reform

To counteract the financial pressure emerging in aging societies, statutory pension schemes are undergoing fundamental reforms in many Western countries. Starting with cohort 1937, Germany introduced permanent pension deductions for early retirement. This study examines the profitability of pension contributions against the background of this reform for cohorts 1935–1945. Internal rates of return (IRR) are used to measure the profitability. For men, the IRR declines from 2.4% to 1.2% and for women from 5.2% to 3.7%. The results suggest that the majority of the trend, about 75–80%, is caused by increased pension contributions and not by the reform.     

ACHIEVING FISCAL BALANCE IN JAPAN*

Japan is aging and has the highest government debt‐to‐output ratio among advanced economies. In this article, we build a micro data‐based, large‐scale overlapping generations model for Japan in which individuals differ in age, gender, employment type, income, and asset holdings, and incorporate the Japanese pension rules. Using existing pension law, current fiscal policy, and medium variants of demographic projections, we produce future paths for government expenditures and tax revenues, with implications for government debt and the public pension fund. Additional pension reform, a higher consumption tax, and higher female labor force participation help achieve fiscal stability.     

The Intergenerational State Education and Pensions

When credit markets to finance investment in human capital are missing, the competitive equilibrium allocation is inefficient. When generations overlap, this failure can be mitigated by properly designed social arrangements. We show that public financing of education and public pensions can be designed to implement an intergenerational transfer scheme supporting the complete market allocation. Neither the public financing of education nor the pension scheme we consider resemble standard ones. In our mechanism, via the public education system, the young borrow from the middle aged to invest in human capital. They pay back the debt via a social security tax, the proceedings of which finance pension payments. When the complete market allocation is achieved, the rate of return implicit in this borrowing–lending scheme should equal the market rate of return.     

生育政策调整、退休年龄延迟与城镇职工基本养老保险最优缴费率

文章基于“十三五”规划建议提出适当降低社会保险费率的现实背景,从社会福利最大化视角,运用一般均衡模型对五种生育情景下不同退休年龄的城镇职工基本养老保险最优社会统筹缴费率进行测算,并分析降低社会统筹缴费率的经济效应。研究表明：（1）最优社会统筹缴费率随退休年龄的延长而下降,随人口增长率的上升而提高。0％－100％符合全面二孩政策规定的妇女生育二孩,使退休年龄为60岁时的最优社会统筹缴费率降到191．8％－196．3％,使退休年龄为65岁时的最优缴费率降到107．7％－116．4％。（2）除了受生育政策和退休年龄影响外,最优社会统筹缴费率对物质资本产出弹性、个人主观效用贴现因子和社会贴现因子的敏感性也较强。（3）降低社会统筹缴费率具有积极的经济效应,不仅能促进经济增长和增进社会福利,而且有助于完善我国多层次养老保险体系。因此,文章为降低城镇职工基本养老保险社会统筹缴费率的改革提供了依据。     

Public Debt and Generational Balance in Austria

Based on Austria's fiscal stance in 1995, wecompute the generational accounts for currently living as well as future generations.The results reveal the existence of an intergenerational imbalance in favor of currentlyliving generations. Total public sector liabilities may be more than five times as high asthe officially recorded level of public debt. Without any action, future generations would facelife-time net taxes that are about 65 percent higher than the tax burden of a current newborn.If the government could fully and permanently retain the expenditure cutting andrevenue raising effects of the 1996 fiscal consolidation package and the 1997 pension reform,then it might be able to significantly reduce the intergenerational liabilities. However,enacting both the recent tax reform 2000 and the reform of the family support scheme wouldincrease again the fiscal imbalance and intergenerational bias of fiscal policy in Austria.     

Public pension and household saving: Evidence from urban China

We relate household savings to pension reform, to explain the high household savings rates in urban China from a new perspective. We use the exogenous – policy-induced – variation in pension wealth to estimate explicitly the impact of pension wealth on household savings, and obtain evidence of a significant offset effect of pension wealth on household savings. Although the size of the effect depends on the parameter values assumed, the finding that household savings are affected by pension reform is robust. Our estimates show that, under plausible scenarios, pension reform boosted household savings rates in 1999 by about 6–9 percentage points for cohorts aged 25–29 and by about 2–3 percentage points for cohorts aged 50–59. Our results also indicate that declining pension wealth reduces expenditure on education and health more than on other consumption items.     

Pension Reform and Economic Performance Under Imperfect Capital Markets

We consider an overlapping generations model where heterogeneous agents take decisions on consumption and investment in education under the assumption of imperfect capital markets. We study how the introduction of a pay-as-you-go and of a fully funded pension scheme affects output and lifetime opportunities, and then analyse the impact of a pension reform. The standard neutrality result for fully funded pension schemes does not hold in this framework. We establish the conditions under which a fully funded scheme is associated with a higher investment in human capital. We show that the transition path may involve poverty traps     

Endogenous retirement and public pension system reform in Spain

Population aging has spurred developed countries around the world to reform their PAYG pension systems. In particular, delaying legal retirement ages and reducing the generosity of pension benefits have been widely implemented changes. This paper assesses the potential success of these policies in the case of the Spanish economy, and compares them with the results obtained by the (rather modest) reforms already implemented in 1997 and 2001. This evaluation is accomplished in a heterogeneous-agent dynamic general equilibrium model where individuals can adjust their retirement ages in response to changes to the pension rules. We check the ability of the model to reproduce the basic stylized facts of retirement behavior (particularly the pattern of early retirement induced by minimum pensions). The model is then used to explore the impact of pension reforms. We find that already implemented changes actually increase the implicit liabilities of the system. In contrast, delaying the legal retirement age and extending the averaging period in the pension formula to cover most of the individual's life-cycle can reduce the implicit liabilities substantially. These findings reveal the failure of the Spanish political system to distribute the costs of population aging more evenly across the generations.     

Demographic change, human capital and welfare

Projected demographic changes in the U.S. will reduce the share of the working-age population. Analyses based on standard OLG models predict that these changes will increase the capital-labor ratio. Hence, rates of return to capital decrease and wages increase, which has adverse welfare consequences for current cohorts who will be retired when the rate of return is low. This paper argues that adding endogenous human capital accumulation to the standard model dampens these forces. We find that this adjustment channel is quantitatively important. The standard model with exogenous human capital predicts welfare losses up to 12.5% (5.6%) of lifetime consumption, when contribution (replacement) rates to the pension system are kept constant. These numbers reduce to approximately 8.7% (4.4%) when human capital can endogenously adjust.     

Italy’s demographic trap: Voting for childcare subsidies and fertility outcomes

In this paper we study how population aging impacts the age distribution of the voting electorate and voters’ choices over childcare subsidies. We build a computable general equilibrium framework populated by heterogeneous agents who, over the course of their life-cycle, make endogenous and age-dependent fertility choices. The model is calibrated to match economic and population outcomes of the Italian economy. Child support favors young and fertile cohorts but can also impact all population subgroups through changes in prices, income taxation and population growth. A probabilistic voting model is used to measure voting outcomes over a range of childcare subsidy levels and tax policies. Our findings show that childcare subsidies have a positive impact on the total fertility rate and are welfare improving when financed with both capital and labor income taxation and in combination with lower pension contribution rates. A 10 percent increase in the level of subsidies can increase the population growth rate by an average of 0.47–0.70 percentage points. We find that voting choices of different population subgroups, while depending on the tax used to finance new expenditure, lead to lower levels of childcare subsidies, lower fertility rates and to a demographic ‘trap’.     

MACROECONOMIC AND REDISTRIBUTIONAL EFFECTS OF CONSUMPTION TAXES IN THE USA*

This paper studies the effect of an increase in consumption taxes using a dynamic general equilibrium model of overlapping generations calibrated to the US economy. When the proceeds are used to reduce income taxes, the reform raises the aggregate capital and labour supply in the long run. Workers increase labour supply immediately in response to the reform, while consumption rises only gradually. The tax reform also transfers wealth from old consumers to young consumers. As a result, while future generations experience significant welfare gains, current generations, particularly old consumers, tend to experience sizable welfare losses. When the proceeds are used for a lump‐sum transfer, the aggregate capital and labour both decrease in the long run. This reform is welfare‐improving for the current low‐income households.     

Risk Sharing and Efficiency Implications of Progressive Pension Arrangements*

This paper aims to quantify the welfare effects of progressive pension arrangements in Germany. Starting from a purely contribution‐related benefit system, we introduce basic allowances for contributions and a flat benefit fraction. Since our overlapping‐generations model takes into account variable labor supply, borrowing constraints as well as stochastic income risk, we can compare the labor supply, the liquidity and the insurance effects of the policy reform. Our simulations indicate that it would be optimal to introduce a flat benefit share of 50 percent and a basic allowance that amounts to 30 percent of average income. Such a reform would yield an aggregate efficiency gain of 3.3 percent of resources.     

Designing the optimal public pension system

This paper uses a two‐period overlapping generations model in order to provide a theoretical design for the optimal public pension system based on a partial equilibrium analysis. Household preferences depend on two periods' consumption and leisure and are positively homogeneous of degree m with respect to consumption in the working and retired periods. We present characteristic features of the optimal public pension system in this paper. First, differences in the population growth rate do not affect the large/small relation between the optimal net lifetime burden rates of generations. Second, we present the optimal public pension system explicitly if m < 1 and m ≠ 0. Third, the difference between the market time‐preference rate and the social time‐preference rate provides a crucial insight into the optimal burden rate of each generation.