---
title: Purchasing Managers' Index (PMI)
description: PMI meaning: what a purchasing managers' index shows, why 50 is the line, the latest ISM and S&P Global US readings, and why traders watch them.
source: Helious
canonical: https://helious.io/learn/pmi
---

# Purchasing Managers' Index (PMI)

A **PMI**, purchasing managers' index, is a monthly survey of company purchasing managers that shows whether business activity is growing or shrinking: a reading above 50 means it grew from the month before, and a reading below 50 means it shrank.

## How a PMI is built

Purchasing managers say whether new orders, output, employment, supplier delivery times and inventories are higher, lower or the same as a month earlier. Each index is the share answering higher plus half the share answering the same, so 50 is the line between growth and contraction. The distance from 50 shows how widespread the change is, not how large it is in dollars.

## ISM and S&P Global

Two families matter in the US. The ISM manufacturing and services PMIs come out on the first and third business days of the month. The S&P Global PMIs come as a flash estimate around the third week of the month and final readings early the next, for manufacturing, services and a composite of the two. Helious tracks both, and scores the surprise against the forecast as each one prints.

## Why traders watch PMIs

PMIs are the first read on each month, out weeks before hard data such as industrial production. The prices-paid and employment questions feed straight into the inflation and payrolls outlook, so a jump in prices paid can move rate expectations even when the headline barely changes.

## Questions

### What does PMI mean?

PMI stands for purchasing managers' index, a monthly survey of purchasing managers. A reading above 50 means activity grew from the month before; below 50 means it shrank.

### Why is 50 the dividing line on a PMI?

Each index is the share of managers reporting an increase plus half the share reporting no change. If as many report a fall as a rise, the index lands at 50.

### What are the latest US PMI readings?

The latest S&P Global and ISM readings, with their release dates and history, are on [the S&P Global PMI page](https://helious.io/data/sp-global-pmi), [the ISM manufacturing page](https://helious.io/data/ism-manufacturing) and [the ISM services page](https://helious.io/data/ism-services).

## Live data

Helious publishes the current figures at [https://helious.io/learn/pmi](https://helious.io/learn/pmi), and through the get_series tool on its MCP server at https://helious.io/mcp.