What is PPI — the inflation gauge that moves before consumer prices
The Producer Price Index (PPI) measures the change in prices that domestic producers receive for the goods and services they sell, sitting one stage earlier in the chain than the Consumer Price Index and therefore read as a leading signal for inflation
The three lines
- PPI is the seller's price, CPI is the buyer's price — the same inflation measured at different stages
- The US release carries two core measures: excluding food and energy, and excluding food, energy and trade services
- The Fed's policy gauge is PCE, but several PCE components draw their source prices from the PPI, not the CPI
Key questions
- What is the Producer Price Index?
- An index measuring how the prices domestic producers receive for their goods and services change over time. Because it is based on what producers receive at the point of shipment rather than what consumers pay at the till, it captures raw materials, intermediate goods and finished output before they reach the consumer. In the US it is published monthly by the Bureau of Labor Statistics; in Korea it is published by the Bank of Korea.
- How is it different from CPI?
- The stage measured and the coverage. PPI is what the seller receives; CPI is what the buyer pays. PPI includes intermediate goods and business-to-business services that consumers never purchase, and excludes imports because those are not domestic producer output. CPI includes imports and reflects final prices with tax and retail margin. So the two can move in different directions in the same month.
- If PPI rises, does CPI have to follow?
- No. The direction often carries through, but not automatically. If input costs rise and firms absorb them by compressing margins, consumer prices need not move; conversely consumer prices can rise on strong demand with flat input costs. In July 2026 US PPI ran at 4.7% year on year against CPI at 3.4% — a 1.3-point gap that can be read either as cost pressure not yet passed on, or as cost pressure firms have decided not to pass on.
- Why are there two core PPI numbers?
- The BLS publishes both. One strips food and energy. The other strips food, energy and trade services — and that is the measure the release itself emphasises. Trade services are wholesale and retail margins, which swing sharply whenever goods prices move fast, so removing them is meant to reveal the underlying trend. In July 2026 the first read +0.2% and the second +0.4%, and markets reacted to the lower one.
Inflation coverage throws several acronyms at once. CPI, PPI, PCE. They arrive within days of each other and sound interchangeable, but they are the same inflation measured at different points in the chain.
PPI is the earliest of the three. It is measured at the factory gate.
1. The definition
The Producer Price Index measures the change in prices that domestic producers receive for the goods and services they sell.
The reference point is what the seller receives — not what a shopper pays.
| Index | Whose price | Which stage |
|---|---|---|
| PPI | What the producer receives | At shipment |
| CPI | What the consumer pays | At the till |
| PCE | What consumers actually spent | From expenditure data |
In the US the Bureau of Labor Statistics publishes it monthly, usually the day after CPI — in August 2026 that was CPI on the 12th and PPI on the 13th. In Korea the Bank of Korea publishes the equivalent series.
2. Three differences from CPI
Stage. PPI sits before distribution, CPI after. Along the chain wheat → flour → bread → shelf, PPI measures the first three links and CPI the last.
Coverage.
| In PPI | In CPI | |
|---|---|---|
| Intermediate goods (steel, chemicals) | ✓ | ✗ |
| Business-to-business services | ✓ | ✗ |
| Imports | ✗ | ✓ |
| Taxes | ✗ | ✓ |
The exclusion of imports is the big one. PPI measures domestic producer output, so a rising price on an imported good never enters it — while the consumer buying that good does show up in CPI.
Which is why the two can diverge. July 2026 in the US is a clean example.
| Index | July 2026 (year on year) |
|---|---|
| PPI | 4.7% |
| CPI | 3.4% |
| Gap | 1.3 points |
Wholesale-stage inflation is running 1.3 points above the consumer stage. That gap admits two readings — cost pressure accumulated but not yet passed through, or cost pressure firms have chosen to absorb in margin. The first implies future CPI increases; the second implies compressed corporate earnings.
3. Why it is called a leading indicator
Input costs take time to reach shelf prices: contracted volumes are used up, new unit costs enter the cost base, and firms decide whether to raise prices.
So a rise in PPI tends to be followed by a rise in CPI months later. Tends to. Two valves sit in between.
| Valve | Effect |
|---|---|
| Corporate margin | Costs rise but are absorbed → consumer prices unchanged |
| Demand | Costs flat but demand strong → consumer prices rise anyway |
Because of those valves, "PPI rose, so CPI will rise" is an assumption, not a forecast. PPI is a signal of possibility, not a booked result.
4. The two core measures
Reading a US PPI release for the first time, the presence of two core numbers is disorienting.
| Measure | What it removes | Rationale |
|---|---|---|
| Core A | Food, energy | Seasonal and oil-driven volatility |
| Core B | Food, energy + trade services | Distribution margins swing wildly when goods prices move |
Trade services are the margins wholesalers and retailers add. When crude falls sharply, a fuel retailer briefly captures a wider margin — and the statistics record that as a rise in services prices, unrelated to the underlying trend. Core B removes it.
The BLS release leads on Core B. Market coverage frequently quotes Core A. July 2026 showed exactly what that divergence costs.
| July 2026 | Month on month |
|---|---|
| Headline | 0.0% |
| Core A (ex food, energy) | +0.2% |
| Core B (also ex trade services) | +0.4% |
Both 0.0% and 0.4% appeared in one release. Equities traded the 0.0%.
5. The route from PPI to interest rates
The Federal Reserve's policy gauge is neither CPI nor PPI but the PCE price index. That would seem to make PPI peripheral.
It does not. Several PCE components take their source prices from the PPI rather than the CPI — portfolio management fees and parts of healthcare among them, because those are not billed to consumers in a form CPI can capture.
The chain:
- PPI records portfolio management fees rising
- That price enters the PCE calculation
- Core PCE prints hotter than expected
- The Fed reads a firmer inflation trend
This is why market participants look past the headline on PPI day and check the PCE-feeding lines. In July 2026 the item driving Core B to 0.4% was precisely portfolio management fees, up 6.5% on the month.
6. Korea's producer price index
The Bank of Korea publishes a monthly series on the same principle: price changes for goods and services supplied by domestic producers to the domestic market.
For Korea, two inputs dominate: the exchange rate and international commodity prices. With most raw materials imported, moves in crude and in the won/dollar rate feed into domestic producer prices relatively quickly. Imported finished goods, by contrast, bypass PPI entirely and show up only in consumer prices.
7. How to read the release — a checklist
| Order | Check | Why |
|---|---|---|
| 1 | Headline MoM | The number markets trade in the first minute |
| 2 | Headline YoY | Trend — compare against the prior month |
| 3 | Core B (ex trade services) | The underlying measure the agency emphasises |
| 4 | Goods vs services | Identifies whether it was an energy effect |
| 5 | PCE-feeding lines | Material for predicting the next PCE print |
Stopping at line 1 is how a reader ends up missing that "inflation stopped" and "the core measure quadrupled" described the same release.
8. What is unresolved
The exact share of core PCE that draws source prices from the PPI could not be determined. That portfolio management fees and parts of healthcare do so is consistent across sources; what fraction of the index that represents is not answered here.
No empirical figure is cited for the average lead time from PPI to CPI. "A few months" is commonly said, but it varies widely by sector and period, and attaching an unverified number would be worse than describing the mechanism.
For the companion piece on the consumer-side gauge, see our explainer on the US CPI.
Sources
- U.S. Bureau of Labor Statistics — Producer Price Index home
- U.S. Bureau of Labor Statistics — Producer Price Index news release
- Wikipedia — U.S. Producer Price Index
- Investing.com — US Producer Price Index (month on month)
- TechTimes — July PPI flat headline hides 0.4% core surge heading into August 26 PCE