Myth: the first spike after a release shows what the number meant

[Shadow Trader]

The belief is simple. The number comes out, price jumps, so the jump is the market's verdict. Reality is messier, and revisions are a big reason why.

Headline figures like jobs or GDP usually come with changes to the previous period. If the new number looks strong but the prior month was revised down by a lot, the net picture can be weak. Algorithms that only parse the headline push price one way. Then humans and slower systems digest the revision and push it the other way. The result is a strange spike followed by a reversal that has no obvious cause on the chart.

Sometimes it works the opposite way: a weak headline paired with an upward revision to the previous month. The first move down gets bought back within a minute or two.

Why does it matter? Because the first move can be driven by whichever number got parsed first, not the one that mattered most. Someone reading the same calendar sees a miss and sells right into the correction.

Checking the revision before reacting is the unglamorous fix, and the habit worth building is looking at the net of headline and revision rather than the headline alone. Even so, the market sometimes cares about the headline anyway, depending on what it was focused on that week.

So the spike is information about speed, not necessarily about meaning.

Has anyone tracked how often a revision flips the direction of the first reaction on the pairs you follow?