Glossary term
ISM Manufacturing PMI
The ISM Manufacturing PMI is a monthly diffusion index that tracks business conditions in the U.S. manufacturing sector.
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What Is the ISM Manufacturing PMI?
The ISM Manufacturing PMI is a monthly index from the Institute for Supply Management that tracks conditions in the U.S. manufacturing sector. It is based on survey responses from purchasing and supply executives at manufacturing companies.
PMI stands for Purchasing Managers' Index. The index is a diffusion index, so it shows whether conditions are broadly improving or worsening across respondents rather than measuring the exact dollar amount of factory output.
Key Takeaways
- The ISM Manufacturing PMI tracks U.S. manufacturing activity each month.
- A reading above 50 generally signals expansion; below 50 signals contraction.
- The report includes detail on new orders, production, employment, supplier deliveries, inventories, prices, and backlogs.
- Markets watch it because manufacturing can turn before broader economic data.
- The index is timely, but it is still survey-based and should be read with other indicators.
How the Index Is Built
ISM surveys manufacturing supply managers about whether business conditions are better, worse, or unchanged. Those responses are converted into index readings. The headline Manufacturing PMI summarizes the direction of activity across key parts of the factory economy.
The subindexes can matter as much as the headline. New orders point to future production demand. Production shows current activity. Employment gives a labor-market signal. Prices can suggest input-cost pressure. Supplier deliveries can be tricky because slower deliveries can reflect either strong demand or supply strain.
Reading the Signal
Reading or detail | Common interpretation |
|---|---|
Above 50 | More respondents report expansion than contraction. |
Below 50 | More respondents report contraction than expansion. |
Rising new orders | Demand may be improving. |
Weak employment | Manufacturers may be slowing hiring or reducing labor needs. |
High prices reading | Input-cost pressure may be building. |
Market Context
Manufacturing is a smaller share of U.S. employment than services, but it remains important for business cycles, capital spending, inventories, trade, commodities, transportation, and corporate earnings. Because the report comes out early each month, investors often use it as a first read on economic momentum.
The index should not be treated as a direct output number. A PMI below 50 does not tell the reader how many units factories produced, and a PMI above 50 does not guarantee strong GDP growth. It shows breadth of expansion or contraction among surveyed companies.
The Bottom Line
The ISM Manufacturing PMI is a timely gauge of factory-sector momentum. It is most useful when readers look beyond the headline and study orders, production, employment, prices, and inventories together.