A plain-English guide to final-demand PPI-to-CPI transmission.

Thursday's analysis piece is the live example. August PPI printed final demand +0.4 percent month-on-month with the diesel wholesale line up +24.1 percent, driven by the Jazan supply shock. The question the desk cares about is not the PPI print itself but the transmission: which of tomorrow's CPI components will move on this PPI signal, on what lag, and with what pass-through coefficient. This reference piece is the framework for reading that transmission.

The three transmission channels

Producer prices transmit to consumer prices through three specific channels, each with its own lag and its own pass-through elasticity. The channels do not overlap cleanly and diagnosing which channel is active matters more than the aggregate PPI print number.

Channel 1: direct pass-through in goods. Wholesale energy prices, wholesale food prices, and wholesale merchandise prices pass through to CPI energy, CPI food, and CPI core goods components with a 30 to 60 day lag and a pass-through elasticity of roughly 0.60 to 0.85. A 10 percent move in the wholesale diesel line typically shows up as a 6 to 8 percent move in the CPI motor fuel line one to two months later, adjusted for the retail-margin dampening. This is the channel that carries the Jazan shock into the September CPI print (not August; the timing is wrong for August).

Channel 2: intermediate-goods embedded cost. Wholesale prices for intermediate materials (steel, chemicals, plastics, packaging) transmit to CPI durable goods with a 90 to 180 day lag and an elasticity of roughly 0.20 to 0.35. A jump in the intermediate goods line today shows up as a modest lift in appliances, furniture, and building materials CPI three to six months out. This is a slow channel and it matters more for the six-month annualised inflation forward path than for the next monthly print. See our six-month annualised framework for how this feeds the strategic view.

Channel 3: services pass-through via input costs. Wholesale services prices (portfolio management fees, healthcare services, air fares, hotel rooms) map into their CPI equivalents with different timing per line, and some lines flow into core PCE more directly than they flow into core CPI. Portfolio management fees have a 30-day lag and near-1.0 pass-through into core PCE (portfolio management fees are a direct input line in PCE), but a much smaller pass-through into core CPI because CPI weights financial services differently. Healthcare services PPI has a 60 to 90 day lag into CPI medical care services with a 0.55 to 0.70 elasticity.

Reading a diesel-driven PPI print

Thursday's print was dominated by the diesel line. Diesel wholesale prices feed retail gasoline prices with a 15 to 30 day lag and an elasticity of roughly 0.55 (retail gasoline responds to wholesale gasoline more strongly than to diesel, but the two move together on a common crude and refined-products basis). The Jazan supply shock has now been in the wholesale price stream for roughly ten sessions; the retail pass-through into the August CPI print (which covers the month ending August 31) is only partial. The larger effect will land in the September CPI print, released mid-October.

That means the August CPI print on Friday September 11 is looking at pre-Jazan wholesale prices for most of the month and post-Jazan wholesale prices for the last week. The energy contribution to August CPI is likely to be modestly hot but not violently so; the full Jazan pass-through arrives in September CPI on October 15.

Traders who treat Thursday's PPI as a "next-day CPI is going to be hot" signal are misreading the transmission timing. The correct read is: Thursday's PPI is a preview of the October CPI print, not of the September CPI print. Friday's CPI is looking at a different window.

The core-goods-vs-services split

The bigger read from Thursday is the split between goods (+1.1 percent) and services (+0.1 percent). Services PPI at +0.1 is dovish; goods PPI at +1.1 is hawkish but concentrated in energy. That composition matters because CPI has been running with services stronger than goods for the last four prints. If the Thursday PPI is the leading indicator, then the composition of the September CPI print (releasing October 15) will look different from the August print (releasing Friday): goods pushing higher, services softer.

For the September FOMC decision on September 16, this is important context. The dot plot will be built on the projected inflation path through the end of 2026. A shift in the composition (goods up, services down) is roughly neutral for headline PCE but slightly hawkish for the specific inflation components the Fed's reaction function weights most heavily.

The four questions to ask on a hot-goods PPI day

1. Is the goods move concentrated in energy or broad-based? Concentrated energy is a supply shock and the Fed looks through it. Broad-based goods is a demand impulse and the Fed reacts to it.
2. What did services do? Services PPI is the closer proxy for the "sticky" inflation the Fed is targeting. A soft services print alongside a hot goods print is dovish on net for the reaction function even when the headline reads hawkish.
3. What is the timing of the wholesale-to-retail lag? The Jazan shock passes through to September CPI, not August. The window matters.
4. Which PCE lines move directly? Portfolio management fees, healthcare services, and air fares transmit into core PCE more directly than into core CPI. If those lines moved on the PPI, the FOMC's core PCE forecast is going to shift by more than the CPI implies.

Related reading

• Thursday's analysis piece: the live example this framework describes.
• PPI vs CPI: the full decomposition of the two inflation gauges.
• PCE vs CPI: why the Fed watches core PCE and not core CPI, and how the PPI-to-PCE map differs from the PPI-to-CPI map.
• CPI components: the OER trick and the specific line items.
• Oil inflation transmission: the crude-to-diesel-to-retail chain the Jazan shock traverses.