Governments across the world are coming under increasing pressure to invest heavily in projects that have maturities of decades or even centuries. Key areas of concern include climate change mitigation, environmental and biodiversity protection, nuclear decommissioning, enhancing infrastructure and coastal defenses, and long-term health care management. Whether such projects are evaluated as being economically justifiable depends on the social discount rate (SDR) that the government deploys. This variable converts the future costs and benefits of public policy into their value today, thereby facilitating the comparison of social investments with different maturities. Critically, the result of such analysis is extremely sensitive to small changes in the choice of the SDR, yet policy guidelines differ widely across countries and international institutions. In this article, we provide a review of the academic literature on long-term SDRs, with particular emphasis on how these insights have been integrated into governmental guidance.

中文翻译：

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未来，现在：社会折扣回顾


世界各国政府面临着越来越大的压力，需要对期限为数十年甚至数百年的项目进行大量投资。关注的关键领域包括减缓气候变化、保护环境和生物多样性、核退役、加强基础设施和海岸防御以及长期医疗保健管理。此类项目是否被评估为经济上合理取决于政府部署的社会贴现率（SDR）。该变量将公共政策的未来成本和收益转化为当前的价值，从而便于比较不同期限的社会投资。至关重要的是，此类分析的结果对特别提款权选择的微小变化极为敏感，但各国和国际机构的政策指导方针却存在很大差异。在本文中，我们回顾了有关长期特别提款权的学术文献，特别强调了如何将这些见解纳入政府指导。