U.S. President Donald Trump’s trade policies have rocked global equities in recent weeks, driving investors to seek out pockets of safety in financial markets.

One of the beneficiaries of the market volatility has been the Swiss franc

, widely seen as a safe haven asset in times of macroeconomic or geopolitical uncertainty. The Swiss currency has appreciated 9.5% against the U.S. dollar since the beginning of the year — but inside Switzerland’s borders, rising demand for the franc is stirring up challenges for policymakers.

The Swiss franc was last seen trading 0.2% lower against the greenback, with $1 buying around 0.82 Swiss francs.

A strong franc puts deflationary pressure on Switzerland. As the currency appreciates, imports – which play a significant role in the country’s economy – become cheaper.