How we get our numbers

Every number comes from the organisation that publishes it, is checked by a script and against the last reading, and goes up with the time we checked it. If something looks wrong, a person looks before it is shown. If a source is late, the page says so.

Where the numbers come from

We take each number from its primary source: the government agency or company that sets it or publishes it first. Interest rate benchmarks come from MAS. CPF rates come from CPF Board, tax rates from IRAS, COE results from LTA, prices and population from SingStat, and bank rates from each bank’s own rates page.

We do not copy numbers from other comparison sites, forums or news reports. When a news story is the first to report a number, we wait for the official release and use that.

The full list of sources, what we take from each and how often, is on Sources.

How often we check

Each number is checked on its publisher’s timetable, not on a fixed one. SORA is checked every working day. T-bill results are checked after each auction. COE results are checked after each bidding exercise. CPF interest rates are checked each quarter, and tax rates when IRAS changes them.

Every tracker page says when it is checked and shows the date and time of the last check, in Singapore Time (SGT, UTC+8).

The checks before a number goes up

A scheduled job fetches each number. Before anything is published, the job checks that:

• the source answered, and the answer looks like the page we expect, not an error page or a redesign;
• the number falls within sensible limits for that series (a savings rate of 40% is a parsing error, not news);
• the change since the last reading is not larger than that series normally moves. A large move is held until a person has compared it with the source;
• the date on the reading is newer than the one we already have, so an old page can never overwrite a new number.

If a check fails, the last good number stays up with its original check time, and we are alerted.

When a source is late or wrong

We never fill a gap with an estimate. If a source has not updated when it should have, the page shows the last official number, with its date, and a note saying the source is late. If a source corrects its own figure, we update ours and say so on the page.

How the calculators work

Calculators use Singapore’s own rules: CPF age bands and wage ceilings, IRAS tax brackets and reliefs for the current year of assessment, and HDB and LTA rules where they apply. Rates come from the same trackers as the rest of the site, never typed in by hand.

Where an agency publishes worked examples (IRAS, CPF Board, HDB and LTA all do), our calculator must reproduce every one of them exactly. These examples are run as tests each time a calculator changes, and the page shows the working, step by step, so you can check it yourself.

History and downloads

Every reading is kept. That is what lets each tracker show a chart, a table and how today compares with the last year. Long series can be downloaded from Data downloads, with a note on how to cite them.

Mistakes

When we get a number wrong, we fix it as soon as we know, and we log it on Corrections: the date, what was wrong, and what it says now. Changes to pages are logged on What’s new. If you spot something, please tell us.

Independence

No bank, agency or product pays for a number, a ranking or a place on a page. The order of any table is set by the number itself (highest rate first, for example), never by a commercial deal. How the site pays for itself is on About.