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What the PMI is
The Purchasing Managers' Index is based on monthly surveys of the managers who buy supplies for businesses. They are asked whether activity such as new orders, production, employment, and deliveries is rising, falling, or steady, and their answers are combined into a single index.
There are separate versions for manufacturing and for services, which together cover most of the economy. Because purchasing managers see changes in demand early, their responses offer a fresh read on conditions.
The all-important 50 line
The PMI is built so that a reading above 50 means the sector is expanding compared with the previous month, and a reading below 50 means it is contracting. The number 50 is the dividing line between growth and decline.
So the first thing to check is simply which side of 50 the reading falls on, and the second is how far from 50 it sits, which hints at how fast the economy is speeding up or slowing down.
💡 Above 50 grows, below 50 shrinks:The 50 level is the single most important thing about the PMI. A move from 52 to 49 is significant because it flips the signal from expansion to contraction, even though the change in the number is small.
Why investors watch it
The PMI is valued for being timely and forward-looking. It is released soon after the month ends, well before figures like GDP, and because purchasing managers respond to demand quickly, it often turns before the broader economy does.
That combination makes it a popular leading indicator for spotting shifts in momentum early, which is why a surprising PMI can move markets.
Its limits
The PMI is a survey of sentiment about direction, not a hard count of output. It tells you whether more managers reported improvement than decline, not by how much production actually changed, so it captures momentum rather than magnitude.
Readings can also differ across regions and providers, and a single month can be noisy, so it is best read as part of a wider dashboard of indicators.
Frequently asked questions
What is the PMI?
The Purchasing Managers’ Index is a monthly survey-based gauge of business activity. Purchasing managers report whether things like new orders and production are rising or falling, and their answers are combined into an index covering manufacturing or services.
What does a PMI above 50 mean?
A reading above 50 means the sector is expanding compared with the previous month, while a reading below 50 means it is contracting. The 50 level is the dividing line between growth and decline, making it the key number to watch.
Why is the PMI considered a leading indicator?
It is released soon after the month ends, earlier than figures like GDP, and purchasing managers tend to see shifts in demand quickly. That makes the PMI a timely, forward-looking read that often turns before the broader economy.
What is the difference between manufacturing and services PMI?
The manufacturing PMI surveys factories and goods producers, while the services PMI covers the much larger services side of the economy. Watching both gives a fuller picture, since the two parts of the economy can move differently.
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