Determinants of Currency Composition of Reserves: a Portfolio Theory Approach

The way central banks manage their foreign reserve assets has evolved over the past decades. One major trend is managing reserves in two or more tranches—liquidity tranche and investment tranche—especially for those with adequate reserves. Incorporating reserve tranching, we have developed in this paper a central bank’s reserve portfolio choice model to analyze the determinants of the currency composition of reserves. In particular, we adopt the classical mean-variance framework for the investment tranche and the asset-liability framework for the liquidity tranche. Building on these frameworks, the roles of currency compositions in imports invoicing and short-term external debt, and risk and returns of reserve currencies can be quantified by our structural model—a key contribution of our paper given the absence of structural models in the literature. Finally, we estimate the potential paths of the share of RMB in reserves under different scenarios to shed light on its status as an international currency.

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Post crisis reflections on Central Bank Reserve Management

"Mechanistic reliance on credit ratings can lead to forced selling in stressed market conditions (thus making the stabilization task of other central banks more difficult) and unintentionally increase concentration risk in the remainder of the portfolio".

http://www.imf.org/en/Publications/WP/Issues/2018/02/16/Central-Bank-Reserve-Management-and-International-Financial-Stability-Some-Post-Crisis-45635

Reserve managers move to equities

¨ ....the question arises as to why the investment tranche (which functions as a long-term investment tool for capital gains purposes) has such large exposure to passive fixed income and cash products. If the investment tranche is designed to produce extra yield in relation to standard bond portfolios, such an allocation seems ineffective. ¨

Diversifying international reserves: a case for going LatAm

Excerpts from the presentation of Juan Foxley-Rioseco at the NALM Seminar for Central Banks   (Singapore, July 2013)  

As we learned from basic portfolio theory, correlations are much more important than individual asset volatility when it comes to appoint suitable candidates for lowering the risk of an asset basket. The lower the better, ideally negative.-

Correlations from historical data suggest that better risk-return frontiers seem achievable if going into local government bonds issued in non-anchor currencies. In fact, Central Banks and Sovereign Wealth Funds are improving their risk-return management by doing exactly that. They should continue to do so as long as liquidity and/or credit risk constraints would not become binding.