In September I kept three economic calendars open side by side and checked them against the official release pages of the statistics offices. I wanted to know three things: are the times right, how fast does the actual number appear, and how do they show revisions.
What I found over about a month:
Times for the big US and UK releases were identical everywhere. For smaller releases, such as Italian or Spanish data, one calendar was an hour off twice, which looked like a time zone mistake on their side.
The actual figure appeared between 2 and about 50 seconds after the release, depending on the calendar. For planning that's fine, for trading the number it's useless. Price is always faster.
Revisions were handled differently. One calendar overwrote the previous value with the revised one without marking it. Another showed both. The third ignored revisions completely.
The revision point matters more than people think. A payrolls number in line with consensus plus a 60k downward revision to the previous month is not an in-line report, and the market treats it that way.
My setup now: one calendar for the weekly plan, the official release page bookmarked for anything I care about, and price itself for the reaction.
Which calendar do others trust for the smaller European releases? That's where I've seen the most errors.
Many economic releases include revisions to the prior period. A payroll report might show a strong new figure and a downward revision of the previous two months that wipes out half of it.
Calendars list the headline figure and the forecast. Revisions are often hidden or shown in a separate column. Traders watching only the main number get surprised when the market goes the opposite way.
The size of revisions matters differently in different regimes. When the market is focused on labor-market cooling, revisions can dominate the reaction. When the focus is elsewhere, they get ignored.
A trader preparing for a release can look at the history of revisions: how large they usually are, and which direction they have tended to go. Sometimes, a consistent pattern appears.
Misreading revisions isn't a minor thing. It's part of why a price can spike on the headline, give it all back within thirty seconds, and then trend the other way.
Fast data sources often show revisions in the same line as the headline. Delayed or simplified feeds may drop them.
Revisions often carry bigger consequences when they change a trend. A report showing three months of upward revisions tells a different story from one showing three months of downward ones. Looking at revisions as a series, not a single number, gives better insight into what the market might be reacting to.
Where does the most reliable view of revisions appear in real time?
