The Straits Times Index (STI) comprises of the stocks of 30 representative companies listed on the Singapore Exchange. The index is calculated based on market-value weighted stock market index.
The Straits Times Industrials Index (STII) was replaced by The Straits Times Index. The index began trading on 31st August 1998 at 885.26 points, the same level where the STII was halt.
The index was constructed by the Singapore Press Holdings, the Singapore Exchange and Professor Tse Yiu Kuen from the Singapore Management University. The formal review of index is done at least once annually, and may also be reviewed on an ad-hoc basis when required.
Criteria for stock inclusion in the Straits Times Index
All classes of the ordinary shares in issue the exchange are eligible for inclusion in the STI. Convertible preference shares and loan stocks are excluded until converted. Companies whose business is that of holding equity and other investments (e.g. Investment Trusts). Free float restrictions apply to all stocks, but the stock has to have at least 15% of the shares being traded on the exchange at any given time. The securities must have a turnover of at least 0.05% of their shares in the market (after the application of any kind of weighting) based on a median daily trade per month in ten of the twelve months of the year.