One interesting topic in the FX market that has been closely studied by both academics and practitioners over the past decade is the violation of the covered interest parity (CIP). CIP is a textbook no-arbitrage condition that states that interest rate differential between two currencies should equal the differential between the forward and spot exchange rates. In other words, in discrete time, we have the following condition:
Where S is the spot exchange rate, F is the forward exchange rate, i is the domestic interest rate and i* is the foreign currency interest rate. The problem is that the above equation has held since the Great Financial Crisis; as it started to become more expensive to borrow US Dollars against most currencies during periods of stress, the cross-currency basis swap (CCBS) has been diverging from zero for the Euro, the British pound and the Japanese Yen. Figure 1 (left frame) shows the evolution of the 3-month CCBS for the three currencies (against the USD) since 2012.
Low interest rates combined with the significant divergence in unconventional monetary policies run by the BoJ and ECB over the years has put pressure on the exchange rates and the CCBS, and therefore has increased the hedging costs for Euro and Japanese investors. The current rate on the US 10Y Treasuries (3.15%) looks certainly very interesting for unhedged international investors (relative to domestic bonds such as in the Euro area or Japan), however changes drastically when we adjust for hedging costs. Figure 2 represents the cash-flows that occur at the start, during the term and at maturity when a Euro investor (A) enters a cross currency basis swap. As you can see, each quarter A pays the 3M USD Libor and receives the 3M Euribor and the basis. Hence, the more negative is the basis, the higher the hedging cost. With the 3M Euribor at -0.316%, the 3M CCBS at -44bps and the 3M Libor USD at 2.61%, the current return on a FX-hedged 10Y US Treasuries is negative (-20bps). Figure 1 (right frame) shows that despite the rise in US yields since the middle 2016, it has been falling for Euro and JPY investors after adjusting for FX hedging costs. A UK investor would get an annual return of 1.35%, which is 15bps below he can get in holding a 10Y Gilt.
Source: Eikon Reuters