PMI and Business Activity

PMI figures are survey-based indices of business activity compiled from the answers of purchasing managers. Their value lies not in precision but in speed: they arrive before official statistics and show direction before it appears in GDP.

The PMI index: what 50 means

The index is built so that 50 separates expansion from contraction, not good from bad. A reading of 52 means activity is growing, without saying how fast. A reading of 48 means contraction. Hence an important subtlety: a fall from 56 to 52 is still growth, merely slower, and reading such a decline as a downturn is wrong.

Why the currency market watches them

Because they lead. Official GDP data arrives weeks and months late; PMI arrives almost immediately after the month ends. For a market trading expectations, an early signal is worth more than an accurate but late one. That is why the reaction to PMI can exceed the reaction to more fundamental but stale figures.

Manufacturing versus services

These are often confused, and the difference is substantial. The manufacturing index is more sensitive to global demand and trade, so it reacts more strongly to external shocks. The services index is closer to domestic consumption and weighs more in developed economies, where services form the bulk of GDP. A divergence between them is informative in itself: it shows where the slowdown sits — at home or in external demand.

Limitations of the measure

PMI is a survey, not a measurement. It reflects managers' perception of change relative to the previous month, and that is its weakness: sentiment can diverge from actual volumes, especially in uncertain periods. Use the index as an indicator of direction and as a reason for market reaction, but not as a precise assessment of the economy's state.

This material is educational and is not individual investment advice. Trading forex carries the risk of losing capital.