GDP data confirms what already happened in the economy, often with a significant lag. PMI surveys, by contrast, are published monthly and ask business managers directly about current conditions, making them one of the fastest available reads on economic momentum.
How PMI Works
Purchasing managers at a representative sample of companies are surveyed each month about new orders, output, employment, prices, and supplier delivery times. The responses are compiled into a single diffusion index.
PMI = (%Improving × 1.0) + (%Unchanged × 0.5) + (%Worsening × 0)The 50 Threshold
A PMI reading above 50 signals expansion in that sector compared to the previous month; below 50 signals contraction. The distance from 50 indicates the pace of change, not an absolute level of output.
| PMI Value | Interpretation |
|---|---|
| Above 50 | Sector expanding |
| Exactly 50 | No change from prior month |
| Below 50 | Sector contracting |
Manufacturing vs. Services PMI
Manufacturing PMI covers factory activity and tends to be more sensitive to global trade cycles. Services PMI covers the much larger share of activity in most developed economies and tends to have a bigger weight in overall growth assessments. A composite PMI blends both.
Why Traders Watch PMI Closely
Because it's released well before GDP and captures forward-looking components like new orders, PMI often provides the first hint that growth is accelerating or slowing. A sustained divergence between two economies' PMI trends is a common driver of medium-term currency trends.
If eurozone PMI is climbing while US PMI is falling, that relative growth divergence often supports EUR/USD over time, independent of any single data point. Cross-country comparison matters more than any one PMI reading in isolation.
GDP: The Confirming Indicator
GDP measures the total value of goods and services produced, typically reported quarterly with preliminary, second, and final estimates. Because it's backward-looking and revised multiple times, it tends to move markets less than PMI or labour data, but it remains the ultimate scorecard for how an economy actually performed.
Other Growth Indicators to Know
- ▸Retail sales — a monthly gauge of consumer spending strength.
- ▸Industrial production — output from factories, mines, and utilities.
- ▸Consumer and business confidence surveys — sentiment gauges that often lead actual spending decisions.