History of Switzerland
Switzerland's most important exports during the war were precision machine tools, watches, jewel bearings (used in bombsights), electricity, and dairy products. During World War Two, the Swiss franc was the only remaining major freely convertible currency in the world, and both the Allies and the Germans sold large amounts of gold to the Swiss National Bank. Between 1940 and 1945, the German Reichsbank sold 1.3 billion francs worth of gold to Swiss Banks in exchange for Swiss francs and other foreign currency.
Foreign-exchange reserves
A case to point out is that of the Swiss National Bank, the central bank of Switzerland. The Swiss franc is regarded as a safe haven currency, so it usually appreciates during market's stress. In the aftermath of the 2008 crisis and during the initial stages of the Eurozone crisis, the Swiss franc (CHF) appreciated sharply. The central bank resisted appreciation by buying reserves. After accumulating reserves during 15 months until June 2010, the SNB let the currency appreciate. As a result, the loss with the devaluation of reserves just in 2010 amounted to CHF 27 Billion or 5% of GDP(part of this was compensated by the profit of almost CHF6 Billion due to the surge in the price of gold). In 2011, after the currency appreciated against the Euro from 1.5 to 1.1, the SNB announced a ceiling at the value of CHF 1.2. In the middle of 2012, reserves reached 71% of GDP.