International Portfolio Optimisation with Integrated Currency Overlay Costs and Constraints

Chatsanga, Nonthachote; Parkes, Andrew J.

Abstract

International financial portfolios can be exposed to substantial risk from variations of the exchange rates between the countries in which they hold investments. Nonetheless, foreign exchange can both generate extra return as well as loss to a portfolio, hence rather than just being avoided, there are potential advantages to well-managed international portfolios. This paper introduces an optimisation model that manages currency exposure of a portfolio through a combination of foreign exchange forward contracts, thereby creating a “currency overlay” on top of asset allocation. Crucially, the hedging and transaction costs associated with holding forward contracts are taken into account in the portfolio risk and return calculations. This novel extension of previous overlay models improves the accuracy of the risk and return calculations of portfolios. Consequently, more accurate investment decisions are obtained through optimal asset allocation and hedging positions. Our experimental results show that inclusion of such costs significantly changes the optimal decisions. Furthermore, effects of constraints related to currency hedging are examined. It is shown that tighter constraints weaken the benefit of a currency overlay and that forward positions vary significantly across return targets. A larger currency overlay is advantageous at low and high return targets, whereas small overlay positions are observed at medium return targets. The resulting system can hence enhance intelligent expert decision support for financial managers.

Citation

Chatsanga, N., & Parkes, A. J. (2017). International Portfolio Optimisation with Integrated Currency Overlay Costs and Constraints. Expert Systems with Applications, 83, 333-349. https://doi.org/10.1016/j.eswa.2017.04.009

• Journal Article Type: Article
• Acceptance Date: Apr 4, 2017
• Online Publication Date: Apr 8, 2017
• Publication Date: Oct 15, 2017
• Deposit Date: Jun 28, 2017
• Publicly Available Date: Jun 28, 2017
• Journal: Expert Systems with Applications
• Print ISSN: 0957-4174
• Electronic ISSN: 0957-4174
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• Volume: 83
• Pages: 333-349
• DOI: https://doi.org/10.1016/j.eswa.2017.04.009
• Keywords: Mean-variance optimisation; Currency overlay; Foreign exchange forward contracts
• Public URL: https://nottingham-repository.worktribe.com/output/887757
• Publisher URL: http://www.sciencedirect.com/science/article/pii/S0957417417302440
• Additional Information: This article is maintained by: Elsevier; Article Title: International portfolio optimisation with integrated currency overlay costs and constraints; Journal Title: Expert Systems with Applications; CrossRef DOI link to publisher maintained version: https://doi.org/10.1016/j.eswa.2017.04.009; Content Type: article; Copyright: © 2017 Published by Elsevier Ltd.
• Contract Date: Jun 28, 2017