Source: Swiss National Bank  

Release: Swiss National Bank Historical Time Series  

Units:  CHF Millions, Not Seasonally Adjusted

Frequency:  Annual

Until 1974, fiduciary business could be recorded on the balance sheet; thereafter, it had to be entered as an off-balance-sheet item.
As of 1981, precious metal accounts are included in the balance sheet.
As of 1992, including non-monetary balance sheet claims and liabilities from lending.
As of 1995, transactions in financial derivatives must be recorded in gross terms, resulting in a significant increase in total assets.
As of 1998, including non-monetary balance sheet claims and liabilities from repo transactions.
As of 2000, the majority of banks have again taken non-monetary claims and liabilities from lending and repo transactions off the balance sheet.

In 1913, certain data which the individual banks had reported in previous years was aggregated due to the creation of new bank categories. Subsequently, this data was recorded in the aggregated form. Consequently, figures are available for big banks as far back as 1906.(Cf. table A1 in the commentary section.
http://www.snb.ch/en/mmr/reference/histz_snb_book/source).
As of 2003, one big bank uses netting, resulting in a marked decrease in its total assets.
In 2004, two big banks switched to US GAAP, resulting in an appreciable increase in their total assets.