Broad price pressure has re-emerged after several months of deflation
Recent dynamics
IGP-M inflation was highly uneven through 2025. After rising 1.06% in February, the index moved between moderate increases and outright declines, including contractions of 1.67% in June and 0.77% in July. This volatility reflected the broader nature of the index and its exposure to producer and commodity prices.
The pattern remained volatile in 2026. Monthly inflation rose sharply to 2.73% in April and remained positive in May before turning negative again in June, July, and August. Those three consecutive declines pointed to a temporary easing in broad price pressure during the middle of the year.
September reversed that pattern decisively. The IGP-M increased 1.57%, following declines of 0.50% in June, 1.16% in July, and 0.22% in August. Despite the sharp monthly rebound, the three-month average remained close to zero, highlighting how quickly the index can change direction from one release to the next.
Interpretation and economic signal
The IGP-M is calculated by FGV IBRE as a weighted combination of three components: the Broad Producer Price Index (IPA), with a 60% weight; the Consumer Price Index (IPC), with a 30% weight; and the National Construction Cost Index (INCC), with a 10% weight.
This composition makes the IGP-M structurally different from consumer-price indicators such as the IPCA. Because producer prices carry most of the weight, movements in agricultural commodities, industrial inputs, exchange rates, and other upstream costs can generate much larger monthly swings in the IGP-M than in household consumer inflation.
The September acceleration illustrates this sensitivity. Producer prices rose sharply, with the IPA increasing 2.08%, while the IPC also returned to positive territory. Raw-material prices were an important source of pressure, particularly agricultural commodities, meaning the rebound was not concentrated in consumer prices alone.
The index also matters beyond its role as an inflation gauge. The IGP-M has historically been used as a reference for adjustments in rental agreements and other contracts, meaning that sustained changes in the index can eventually affect contractual prices even when its short-term movements differ from the IPCA.
Conclusion
The latest IGP-M reading marks a clear reversal from the deflation observed over the previous three months. The return to a strong positive monthly rate signals renewed broad price pressure, led primarily by the producer side of the index and accompanied by firmer consumer prices.
The signal should nevertheless be interpreted with caution because the IGP-M is inherently volatile and highly exposed to commodity and upstream-price movements. Persistence across subsequent releases will be more important than a single monthly rebound in determining whether the latest increase represents a broader inflationary trend or another temporary swing in wholesale prices.