Historical index-change calculator
Compares two user-entered observations from the same series. Dividends, fees and any tracking product are outside the calculation.
Historical comparison ready.
The annualised rate mathematically smooths the earlier and later levels. It does not mean the index changed by that percentage in each intervening year and it is not a forecast.
All investments carry risk, including loss of the full amount involved, and may not suit everyone. Historical index levels and percentage changes do not indicate future performance. This page supplies no tradable quote, product selection or personalised recommendation.
A useful way through this page
- Name the exact index series and dates being compared.
- Use like-for-like levels to calculate points and percentage change.
- Keep price return, total return, breadth and trading value separate.
“The Singapore market rose” can mean several things
The Straits Times Index may rise while most listed counters fall. Trading value may jump while the index barely moves. A price index can also show a different result from a dividend-inclusive series. Use SGX for the current official screen and MAS Monthly Statistical Bulletin table III.7 for historical index, listing, turnover and capitalisation data.
What the STI measures
The STI is a free-float-adjusted, market-capitalisation-weighted benchmark of 30 top eligible companies within the FTSE ST All-Share universe. A larger eligible constituent has more influence than a smaller one, so index direction need not match the count of rising and falling shares.
It is not the whole market: it excludes many Mainboard companies and the separate Catalist universe, although eligible REITs can be constituents. The index level is not a dollar price, and this page lists no tracking product.
How to read a market snapshot
| Number | What it answers | What it does not answer |
|---|---|---|
| STI level | Where the benchmark stands | Whether every Singapore share rose |
| Point change | Absolute move from the comparison level | Whether the move was large proportionally |
| Percentage change | Relative movement over the stated period | Dividend-inclusive change unless specified |
| Trading volume | Units traded | SGD value of those trades |
| Trading value | Monetary value of transactions | One holder’s outcome after costs and distributions |
| Advancers and decliners | Breadth across counters | The size or index weight of each move |
| Market capitalisation | Aggregate equity value under the method | Cash available to holders |
Always match date, time, currency and comparison basis. An intraday percentage normally compares with the previous close; a multi-year percentage needs like-for-like observations from the same series.
Price return is not total return
A price index tracks price changes. A total-return index also reflects distributions under the index provider’s methodology. Do not add an arbitrary distribution rate to the STI price result and call it an official total-return figure. Use the same official series at both dates.
For the deliberately negative default move from 4,000 to 3,200, the point change is −800 and the cumulative percentage change is −20%. Across five years, the smoothed annualised rate is −4.36%. It is index arithmetic only, not the outcome of owning a product.
large, mid and small cap
30 top eligible companies
separate from the STI selection universe
Series and release checks before comparing two dates
These labels determine what the number means. They are more durable than copying an un-timestamped index level.
| Field | What to record |
|---|---|
| Series | Price index or total-return index; do not splice them |
| Universe | STI, FTSE ST All-Share, Catalist or another named series |
| Currency | The FTSE ST benchmark base currency is SGD |
| Constituent weighting | Free-float-adjusted market capitalisation under the ground rules |
| Observation | Exact date, time and end-of-day or intraday status |
| Review | Constituent reviews can change the basket; record the effective date |
A short Singapore market timeline
| Date | Milestone |
|---|---|
| December 1966 | The Straits Times Industrials Index, the STI’s precursor, began |
| August 1998 | The Straits Times Index launched with 55 constituents |
| 2007–2008 | FTSE, SGX and SPH overhauled the index family and adopted FTSE methodology |
| 2008 | The STI moved to 30 constituents |
| 4 June 2026 | The quarterly review announced no constituent changes, effective 22 June |
Market structure, constituents and index methodology change over long periods. A historical milestone is context, not a performance argument.
Data and update methodology
- SGX for the official market screen, constituents and trading rules.
- MAS for official historical statistics and policy statements.
- Index-provider documents for methodology.
- Company announcements for event-specific explanations.
No quote table or constituent feed is scraped or republished. The calculator contains no market feed, monetary simulation or forecast; it only compares two user-entered levels from what should be the same named series.
Primary sources
- SGX — Straits Times Index
- LSEG / FTSE Russell — FTSE ST Index Series and ground rules
- SGX — June 2026 STI quarterly review
- MAS — Historical SGX market statistics
- MAS — 2025 Singapore equities market performance
- MAS — STI 60th anniversary
- MAS — November 2025 securities traded value
- MAS — Equities Market Review, 2025
- SGX Rulebook — Regulatory Notice 8.2.1, trading hours and phases
Last fact-checked: 3 September 2026. Rules, fees and official pages can change; check the linked source before acting.