The Swiss Market Index (SMI) is Switzerland's blue-chip stock market index, which makes it the most important in the country. It is made up of twenty of the largest and most liquid SPI large- and mid-cap stocks. As a price index, the SMI is not adjusted for dividends, but a performance index that takes account of such distributions is available (the SMIC - SMI Cum Dividend).

The SMI was introduced on 30 June 1988 at a baseline value of 1500 points. Its composition is examined once a year. Calculation takes place in real-time: as soon as a new transaction occurs in a security contained in the SMI, an updated index level is calculated and displayed.

The securities contained in the SMI currently represent more than 90% of the entire market capitalisation, as well as of 90% trading volume, of all Swiss and Liechtenstein equities listed on the SWX Swiss Exchange. Because the SMI is considered to be a mirror of the overall Swiss stock market, it is used as the underlying index for numerous derivative financial instruments such as options, futures and index funds (e.g. ETFs).

• Acceptance criteria: To be accepted into the SMI, a given issue must meet stringent requirements with regard to liquidity and market capitalisation. On one hand, it must represent at least 50% of the average liquidity of the SPI constituent issues and, on the other, have a minimum free-float capitalisation equal to 0.45% or more of the entire SPI capitalisation. Moreover, trading volume and capitalisation are the determining factors in the quarterly rankings.

• Restructuring: The SMI comprises a fixed number of 20 securities as of the ordinary review date in September 2007. Prior to this date, the index contained 25 listings. The ranking as of 30 June 2007 (according to average capitalisation and the turnover achieved during one year, i.e. from 1 July 2006 through 30 June 2007) determined which companies would remain within the SMI. On 2007-07-05, SWX announced that Ciba Specialty Chemicals, Lonza Group, Givaudan, SGS and one of the two classes of shares of Swatch Group would leave the SMI as of 2007-09-24, leaving 20 securities in the index.