Why surprises, not numbers, move prices

The most important idea in trading economic data is this: markets move on surprises, not on the number itself. A "good" number can send a currency down, and a "bad" one can send it up. Understanding why is what separates a confused reaction from a confident one.

Markets price the expectation in advance

Before any major release, economists publish a consensus forecast — the market's expectation. By the time the data comes out, the expected outcome is already priced in. The market only reacts to the gap between actual and expected:

• Actual better than expected → a positive surprise → the currency usually strengthens (for growth/inflation data that implies higher rates).
• Actual worse than expected → a negative surprise → the currency usually weakens.
• Actual in line with expectations → often little reaction, even if the number looks dramatic.

"Buy the rumor, sell the fact"

This old saying captures it: a currency can rally for weeks on the expectation of good news, then fall the moment the good news is confirmed — because the move already happened and traders take profits. The event itself is the exit, not the entry.

The practical rule

Never trade a release by asking "is this number good or bad?" Ask "is this better or worse than the market expected, and was that already priced in?" The consensus figure on the economic calendar is the benchmark every actual number is judged against — which is exactly what the final lesson shows you how to use.