How to check whether a financial number you just read is still true

This is the method this publication uses on itself. We are publishing it because it works on anything — a headline, a chart on social media, a figure in a sales pitch — and because nothing in it requires a subscription or a terminal.

Five questions. Most figures fail one of them.

1. Which two dates does it have?

Confusing the two is the single most common error in financial writing, and it runs in both directions: presenting an old figure as current, and dismissing a current figure as old because the period it covers has passed.

So ask both. If the article gives you neither, that is information about the article.

2. Who issued it?

Almost every US economic number traces back to a small number of agencies. The outlet you read it in is a courier, not a source.

Knowing the cadence is most of the work. A mortgage rate from three weeks ago has been superseded twice. A CPI figure from three weeks ago is almost certainly still the latest one published.

3. Has it been revised?

Survey-based figures are re-estimated as more of the survey comes in. The first print is a draft, and the revision is often larger than the number everyone argued about.

The rule that follows: for any survey figure more than a month old, check the latest release rather than the one that made the news. The agency publishes the revision in the next month's report, usually in a table most coverage skips.

4. Does it have an error bar?

Census goes further and marks the figures where, in its own words, there is insufficient statistical evidence to conclude the change is different from zero. Those marks are printed in the release and almost never survive into coverage.

5. Has inflation been taken out?

Some series are adjusted for price changes and some are not, and the release always says which. Retail sales are not: the Census Bureau states that the estimates are adjusted for seasonal variation and trading-day differences “but not for price changes”. That makes a six percent annual rise into about two and a half percent once the 3.4% price level is removed.

• Nominal means the dollars actually spent. Sales, revenue and wages are usually reported this way.
• Real means after the price level has been taken out. GDP growth is usually reported this way.
• The conversion is division, not subtraction: 6.0% nominal against 3.4% inflation is 2.5% real, not 2.6%.
• When a release does not say, assume nominal and look it up.

Doing it in about a minute

1. Name the figure and the agency. “Retail sales” becomes “the Census Bureau's advance monthly retail trade report”.
2. Find the agency's own release. Search the agency name plus the report name. The agency page ranks above the coverage almost every time, and it is free.
3. Read the top of it. The period, the publication date, the margin of error and the revision to the previous month are all in the first page.
4. Check the calendar for the next one. The Bureau of Labor Statistics and the Census Bureau both publish release schedules a year in advance, so you can see whether a newer figure exists yet.
5. Write the date down next to the number. If you take one habit from this, take that one.

What we do with this

Every figure on this site carries the date it was observed, and the data status page lists when each one was last confirmed and what happens when a feed stops updating. Where a published figure has since been revised, the corrections page records it rather than editing the number quietly. And a companion piece sets out every figure this site was relying on and the day each one arrived.