IDEAS home Printed from https://ideas.repec.org/p/pra/mprapa/63437.html
   My bibliography  Save this paper

When should the distant future not be discounted at increasing discount rates?

Author

Listed:
  • Szekeres, Szabolcs

Abstract

A number of governments have already adopted the policy of applying Declining Discount Rates (DDRs) to long lived projects, a move that will significantly affect public sector investment decisions. This paper argues that such policy is misguided, and revisits the discussion that led to it. A 2009 paper by Christian Gollier and Martin L. Weitzman is widely regarded as having solved the Weitzman-Gollier Puzzle, which is that the definition of expected present value (EPV) proposed by Weitzman’s in 1998 is inconsistent with the calculation of expected future values (EFV) when market interest rates are stochastic but perfectly auto-correlated. The inconsistency is actually due to the fact that Weitzman’s EPV formulation is incorrect. When it is replaced by the correct formulation, the puzzle disappears, and risk neutral certainty equivalent rates (CERs) turn out to be growing, rather than declining under the assumptions of Weitzman’s model. This removes the justification for the use of DDRs. This paper shows that Gollier and Weizmann (2009) fail to resolve the puzzle. Adding risk aversion to Weitzman’s 1998 model to derive risk adjusted CERs cannot resolve the inconsistency between alternative methods of computing expected monetary yields, because investors’ risk aversion only affects their own valuations, not market yields. If monetary CERs increase, the underlying efficiency of investment projects must generally match the growing monetary CERs of capital markets for them to be worth investing in, even for risk averse investors. The distant future should only not be discounted at increasing discount rates if Weitzman’s 1998 assumption of perfectly auto-correlated interest rates fails to hold sufficiently.

Suggested Citation

  • Szekeres, Szabolcs, 2015. "When should the distant future not be discounted at increasing discount rates?," MPRA Paper 63437, University Library of Munich, Germany.
  • Handle: RePEc:pra:mprapa:63437
    as

    Download full text from publisher

    File URL: https://mpra.ub.uni-muenchen.de/63437/1/MPRA_paper_63437.pdf
    File Function: original version
    Download Restriction: no
    ---><---

    References listed on IDEAS

    as
    1. Gollier, Christian, 2004. "Maximizing the expected net future value as an alternative strategy to gamma discounting," Finance Research Letters, Elsevier, vol. 1(2), pages 85-89, June.
    2. Gollier, Christian & Weitzman, Martin L., 2010. "How should the distant future be discounted when discount rates are uncertain?," Economics Letters, Elsevier, vol. 107(3), pages 350-353, June.
    3. Maureen L. Cropper & Mark C. Freeman & Ben Groom & William A. Pizer, 2014. "Declining Discount Rates," American Economic Review, American Economic Association, vol. 104(5), pages 538-543, May.
    4. Wolfgang Buchholz & Jan Schumacher, 2008. "Discounting the Long-Distant Future: A Simple Explanation for the Weitzman-Gollier-Puzzle," CESifo Working Paper Series 2357, CESifo.
    5. Ben Groom & Cameron Hepburn & Phoebe Koundouri & David Pearce, 2005. "Declining Discount Rates: The Long and the Short of it," Environmental & Resource Economics, Springer;European Association of Environmental and Resource Economists, vol. 32(4), pages 445-493, December.
    6. Weitzman, Martin L., 1998. "Why the Far-Distant Future Should Be Discounted at Its Lowest Possible Rate," Journal of Environmental Economics and Management, Elsevier, vol. 36(3), pages 201-208, November.
    7. Szekeres, Szabolcs, 2015. "Governments Should Not Use Declining Discount Rates in Project Analysis," MPRA Paper 63438, University Library of Munich, Germany.
    Full references (including those not matched with items on IDEAS)

    Citations

    Citations are extracted by the CitEc Project, subscribe to its RSS feed for this item.
    as


    Cited by:

    1. Szekeres, Szabolcs, 2015. "The Mechanics of the Weitzman-Gollier Puzzles," MPRA Paper 64286, University Library of Munich, Germany.
    2. Szekeres, Szabolcs, 2015. "Governments Should Not Use Declining Discount Rates in Project Analysis," MPRA Paper 63438, University Library of Munich, Germany.

    Most related items

    These are the items that most often cite the same works as this one and are cited by the same works as this one.
    1. Gollier, Christian, 2016. "Gamma discounters are short-termist," Journal of Public Economics, Elsevier, vol. 142(C), pages 83-90.
    2. Freeman, Mark C. & Groom, Ben & Panopoulou, Ekaterini & Pantelidis, Theologos, 2015. "Declining discount rates and the Fisher Effect: Inflated past, discounted future?," Journal of Environmental Economics and Management, Elsevier, vol. 73(C), pages 32-49.
    3. Szekeres, Szabolcs, 2015. "The Mechanics of the Weitzman-Gollier Puzzles," MPRA Paper 64286, University Library of Munich, Germany.
    4. Wolfgang Buchholz, 2014. "Discounting in an Uncertain World - Disentangling the Debate on the Weitzman-Gollier Puzzle," CESifo Working Paper Series 4967, CESifo.
    5. Lanlan Luo & Shou Chen & Ziran Zou, 2020. "Determining the Generalized Discount Rate for Risky Projects," Environmental & Resource Economics, Springer;European Association of Environmental and Resource Economists, vol. 77(1), pages 143-158, September.
    6. Fesselmeyer, Eric & Liu, Haoming & Salvo, Alberto, 2016. "How Do Households Discount over Centuries? Evidence from Singapore's Private Housing Market," IZA Discussion Papers 9862, Institute of Labor Economics (IZA).
    7. Kollenberg, Sascha & Taschini, Luca, 2016. "Emissions trading systems with cap adjustments," Journal of Environmental Economics and Management, Elsevier, vol. 80(C), pages 20-36.
    8. Szekeres, Szabolcs, 2020. "Correcting the Error in Gamma Discounting," MPRA Paper 102232, University Library of Munich, Germany, revised 27 Jul 2020.
    9. Eric Fesselmeyer & Haoming Liu & Alberto Salvo, 2022. "Declining discount rates in Singapore's market for privately developed apartments," Journal of Applied Econometrics, John Wiley & Sons, Ltd., vol. 37(2), pages 330-350, March.
    10. Desheng Wu & Shuzhen Chen, 2017. "Benchmarking Discount Rate in Natural Resource Damage Assessment with Risk Aversion," Risk Analysis, John Wiley & Sons, vol. 37(8), pages 1522-1531, August.
    11. Rafał Buła & Monika Foltyn-Zarychta, 2022. "Declining Discount Rates for Energy Policy Investments in CEE EU Member Countries," Energies, MDPI, vol. 16(1), pages 1-27, December.
    12. Moritz Drupp & Mark Freeman & Ben Groom & Frikk Nesje, 2015. "Discounting disentangled: an expert survey on the determinants of the long-term social discount rate," GRI Working Papers 196a, Grantham Research Institute on Climate Change and the Environment.
    13. Freeman, Mark C. & Groom, Ben, 2016. "How certain are we about the certainty-equivalent long term social discount rate?," Journal of Environmental Economics and Management, Elsevier, vol. 79(C), pages 152-168.
    14. Traeger, Christian P., 2012. "What's the Rate? Disentangling the Weitzman and the Gollier Effect," CUDARE Working Papers 121932, University of California, Berkeley, Department of Agricultural and Resource Economics.
    15. Fleurbaey, Marc & Zuber, Stéphane, 2015. "Discounting, risk and inequality: A general approach," Journal of Public Economics, Elsevier, vol. 128(C), pages 34-49.
    16. Rick van der Ploeg, 2020. "Discounting and Climate Policy," CESifo Working Paper Series 8441, CESifo.
    17. Szekeres, Szabolcs, 2016. "Testing Gollier and Weitzman’s Solution of the “Weitzman-Gollier Puzzle”," MPRA Paper 72593, University Library of Munich, Germany.
    18. Jouini, Elyès & Marin, Jean-Michel & Napp, Clotilde, 2010. "Discounting and divergence of opinion," Journal of Economic Theory, Elsevier, vol. 145(2), pages 830-859, March.
    19. Buchholz Wolfgang & Heindl Peter, 2015. "Ökonomische Herausforderungen des Klimawandels," Perspektiven der Wirtschaftspolitik, De Gruyter, vol. 16(4), pages 324-350, December.
    20. Bartolini, Stefano & Sarracino, Francesco, 2018. "Do People Care About Future Generations? Derived Preferences from Happiness Data," Ecological Economics, Elsevier, vol. 143(C), pages 253-275.

    More about this item

    Keywords

    Discount rate; uncertainty; declining discount rate; benefit-cost analysis; negative compounding.;
    All these keywords.

    JEL classification:

    • D61 - Microeconomics - - Welfare Economics - - - Allocative Efficiency; Cost-Benefit Analysis
    • H43 - Public Economics - - Publicly Provided Goods - - - Project Evaluation; Social Discount Rate

    NEP fields

    This paper has been announced in the following NEP Reports:

    Statistics

    Access and download statistics

    Corrections

    All material on this site has been provided by the respective publishers and authors. You can help correct errors and omissions. When requesting a correction, please mention this item's handle: RePEc:pra:mprapa:63437. See general information about how to correct material in RePEc.

    If you have authored this item and are not yet registered with RePEc, we encourage you to do it here. This allows to link your profile to this item. It also allows you to accept potential citations to this item that we are uncertain about.

    If CitEc recognized a bibliographic reference but did not link an item in RePEc to it, you can help with this form .

    If you know of missing items citing this one, you can help us creating those links by adding the relevant references in the same way as above, for each refering item. If you are a registered author of this item, you may also want to check the "citations" tab in your RePEc Author Service profile, as there may be some citations waiting for confirmation.

    For technical questions regarding this item, or to correct its authors, title, abstract, bibliographic or download information, contact: Joachim Winter (email available below). General contact details of provider: https://edirc.repec.org/data/vfmunde.html .

    Please note that corrections may take a couple of weeks to filter through the various RePEc services.

    IDEAS is a RePEc service. RePEc uses bibliographic data supplied by the respective publishers.