The USD/CHF pair, colloquially referred to as the "Swissy", currently offers one of the strongest interest rate spreads among all positive-carry currency pairs. Naturally, this should provide continued support for the pair over time, as it effectively costs money to hold Swiss francs in terms of U.S. dollars; better to sell the Swiss francs in order to purchase U.S. dollars to benefit from the positive interest rate differential.
The chart below provides us with a long-term view of the U.S. dollar, expressed in terms of the Swiss franc. The USD/CHF pair has enjoyed an extended