The Purchasing Managers Index (PMI) is arguably the most important single leading indicator in global finance. Released monthly, it surveys thousands of purchasing managers across manufacturing and services companies and asks them whether business conditions have improved, stayed the same, or worsened since the previous month. The result — a simple number above or below 50 — is one of the earliest and most reliable signals of where the global economy is heading, and it directly drives commodity prices, shipping rates and cyclical stock valuations.
What Is the PMI and How Is It Calculated
The Purchasing Managers Index is compiled by S&P Global (formerly IHS Markit) through monthly surveys of purchasing managers — the people responsible for ordering supplies and materials in manufacturing and service companies. They are asked whether conditions across five categories have improved, stayed the same, or deteriorated versus the previous month.
The five components for the manufacturing PMI are: new orders (weighted 30%), output (25%), employment (20%), suppliers' delivery times (15%) and inventories of purchases (10%). Each component score is calculated as: (% reporting improvement) + (0.5 × % reporting no change). The five components are then combined using their weights to produce the composite PMI.
A PMI above 50 indicates that more managers reported improvement than deterioration — the manufacturing sector is expanding. Below 50 means more managers reported worsening conditions — the sector is contracting. The distance from 50 indicates the pace of expansion or contraction: a PMI of 55 is a stronger expansion than 51.
How to Read a PMI Number
The PMI is both a level indicator and a directional indicator — and the direction is often more important than the level for investment decisions.
Level signals: Above 55 = strong expansion (typically positive for cyclical stocks and commodities). 50-55 = moderate expansion (neutral to mildly positive). 45-50 = mild contraction (caution signal for cyclicals). Below 45 = severe contraction (sell signal for most cyclicals and commodities). Below 40 = acute crisis (as in COVID April 2020 at 27 — a buy signal for long-term investors).
Direction signals: A PMI rising from 47 to 51 is more positive for cyclical stocks than a PMI of 55 that is falling from 58. Rising means conditions are improving sequentially. Falling means they are deteriorating sequentially. The best commodity buy signal is a PMI that has bottomed below 48 and is rising — this is when to add to copper, shipping and energy positions.
PMI recovering from below 48 — combined with commodity prices near their cycle lows — is the most reliable buy signal across all commodity sectors. In 2016 (PMI recovered from 50.1 trough), 2020 (PMI recovered from 39.6 COVID low) and 2022 (PMI recovered from 49.6), investors who bought commodity stocks at PMI trough made 200-400%+ returns over the following 12-24 months.
Global PMI vs Caixin PMI vs ISM
Several PMI measures exist simultaneously and provide different views on the global economy:
Global Manufacturing PMI (S&P Global / JPMorgan): The broadest measure, covering 30+ countries. The Signycle PMI signal at 51.4 refers to this composite measure. It is the best single indicator of global commodity demand.
Caixin China Manufacturing PMI: China-specific, covering private sector manufacturers. This is the most important sub-PMI for commodity investors — because China drives 40-55% of demand for most industrial commodities. When Caixin PMI is above 50 and rising, commodity demand is healthy. The Caixin PMI is published one day before the official Chinese NBS PMI and often gets more market attention.
ISM Manufacturing (US): The US PMI equivalent, published by the Institute for Supply Management. The ISM uses a different methodology from S&P Global but provides similar directional signals. Above 50 = US manufacturing expansion. The ISM also publishes a prices paid sub-index — when this is above 60, commodity input cost inflation is accelerating.
Eurozone Manufacturing PMI: Particularly important for Frankfurt-listed stocks (Siemens, BASF, Volkswagen) and for Norwegian exporters. The Eurozone PMI directly drives BASF's chemical order volumes and Siemens' industrial equipment demand.
How the PMI Affects Different Stock Sectors
| Sector | PMI sensitivity | Signal level | Key stocks |
|---|---|---|---|
| Copper miners | Very high — copper = industrial metal | Above 52 = strong positive | Freeport (FCX), Jiangxi Copper — current PMI 51.4 |
| Steel producers | Very high — steel = construction/manufacturing | Above 51 = positive | Nucor (NUE), Thyssenkrupp, Baoshan Iron |
| Shipping (dry bulk) | High — trade volume tracks PMI | Above 51 = BDI positive | Golden Ocean — current BDI 2567 |
| Oil services | High — drilling = capex decision tracks PMI | Above 52 = capex expansion | Halliburton, SLB, Transocean |
| Airlines | Medium-high — business travel tracks PMI | Above 51 = cargo/business class growth | SIA (C6L), Lufthansa — flying 104 |
| Singapore banks | Medium — loan growth tracks manufacturing | Above 51 = positive for UOB ASEAN loans | DBS, OCBC, UOB — current PMI 51.4 |
| Fertilizers | Medium — agricultural PMI-linked | PMI affects food demand indirectly | Yara, Mosaic, CF Industries |
| REITs (industrial) | Medium — logistics/warehouse demand | Above 52 = industrial REIT positive for Mapletree | Mapletree Industrial, CapLand Ascendas |
Using PMI as a Cycle Timing Tool
The PMI is most useful as a cycle timing tool when combined with commodity price signals. The four quadrant framework for PMI + commodity price:
Quadrant 1: PMI rising + commodity prices low — Best commodity stock entry point. This is early cycle. Buy copper miners, shipping, oil E&Ps. This was March-June 2020 (PMI recovering, Brent $20-40) and early 2016 (PMI recovering, Brent $27-45).
Quadrant 2: PMI rising + commodity prices rising — Mid cycle. Hold winners. Add on dips. This was 2021 as PMI recovered from COVID and commodities surged.
Quadrant 3: PMI falling + commodity prices high — Late cycle warning. Current approximate position. PMI at 51.4 is not falling yet, but Brent $107 and copper $13,213 are elevated. Take profits on highest-leverage names.
Quadrant 4: PMI falling + commodity prices falling — Full contraction. Sell remaining commodity exposure. Hold cash. This was 2015-2016 and 2019 (pre-COVID).
What Does PMI 51.4 Mean Right Now?
The current global PMI at 51.4 is marginally positive — manufacturing activity is expanding at a slow but positive pace. This is consistent with the Signycle cycle score of 76/100 (Late Expansion): positive enough to support commodity demand, but not accelerating enough to drive a new bull market leg.
The key question is whether PMI will accelerate above 53 (positive for commodities and cyclicals) or decelerate below 50 (negative). The Hormuz crisis has added an unusual inflation shock that could push PMI down through reduced consumer spending power — or push it up through emergency infrastructure and defence spending. This is the central uncertainty in the current cycle.
For investors: at PMI 51.4, commodity stocks are in a holding pattern. Do not add aggressively to positions (late cycle), but do not panic sell (PMI is still positive). Monitor the monthly PMI release closely — a fall below 49 would be the signal to meaningfully reduce commodity exposure.
Not financial advice. See disclaimer.