The Swiss central bank said Friday it expected to post a loss of 23 billion Swiss francs ($23 billion, 21 billion euros) for 2015, hit mainly by the hefty depreciation of its foreign currency holdings.

The Swiss National Bank said it had lost a full 20 billion francs on its foreign currency positions, and another four billion on its gold holdings.

Those losses were slightly offset by a one-billion-franc profit made on the bank's Swiss franc positions, it said.

Despite the deep losses, the bank said it would post a balance sheet profit thanks to a 27.5-billion-franc distribution reserve.

It said it would therefore be able to dish out a dividend of 15 Swiss francs per share, and would distribute one billion francs to the Swiss Confederation and cantons.

The central bank's definitive 2015 figures will be released on March 4.

Friday's announcement came nearly a year after the central bank's shock decision to halt its pricy three-year-bid to artificially hold down the value of the franc against the euro.

The decision to scrap the limit sent the franc -- a refuge currency -- soaring in value against major currencies and unleashed turbulence on global markets.

Last June, the central bank was forced to intervene to stabilise the markets, as investors frightened by the chaos in Greece flocked to the franc, hurting Switzerland's export-oriented economy by making the country's products more expensive.