The Swiss franc appreciated vis-à-vis the U.S. dollar today as the greenback tested bids around the CHF 1.0770 level and was capped around the CHF 1.0895 level. Data released in Switzerland yesterday saw the January trade surplus climb to  CHF 2.42 billion from CHF 1.36 billion in December.  Also, the ZEW February expectations survey fell to 52.5 from 56.2 in January.  Dealers this week again speculated the Swiss National Bank sold francs for euro in an intervention to help Swiss foreign trade.  Many dealers believe the Swiss National Bank will not be able to prevent the Swiss U.S. dollar offers are cited around the CHF 1.0930 level.  The euro moved lower vis-à-vis the Swiss franc as the single currency tested bids around the CHF 1.4640 level while the British pound depreciated vis-à-vis the Swiss franc and tested bids around the CHF 1.6655 level.