The Association of Foreign Banks in Switzerland's data exhibited a decline in foreign-owned Swiss banks. 145 banks were listed at start of 2012. This dropped to 129 by the end of May. In five years, assets went down by a quarter to CHF870.7 billion or US$921 billion. Clients' withdrawal of money and paid taxes on unspecified accounts were accounted for the fall.

According to the experts interviewed by Bloomberg News, bank secrecy's crackdown might open up mergers and acquisitions. An enhanced regulatory inspection may also help in the next 12 to 18 months.

Boston Consulting Group said Switzerland's status would weaken if withdrawals continue. The Alpine republic has US$2.2 trillion or about 26% of the global offshore wealth.  

"There will be a bit of a shakeout among private banks," Felix Wenger, a Zurich-based director and co-head of the private-banking practice at consulting firm McKinsey & Co. stated. "Specifically for Switzerland, some foreign players might conclude that an exit is a better option."