The consensus reads the August durable goods figures as a broadly positive manufacturing story. The detail underneath that reading is more specific (and more inflationary) than most coverage has acknowledged. Core capital goods orders rose 1.6% in August from July and 14.1% year-over-year, reaching $88 billion, according to the U.S. Census Bureau‘s advance report, released 26 September 2024. The category strips out defence and aircraft, making it a cleaner read on underlying business investment than the headline durable goods number.
What the Headline Durable Goods Number Obscures
Headline durable goods orders (all categories including aircraft and defence) were unchanged in August from July at $339 billion, seasonally adjusted. That flat reading drew most of the attention. What drove it was a sharp drop in transportation equipment, and specifically nondefense aircraft and parts, which declined 4.3% in August, according to tEDmag. Aircraft orders are notoriously volatile: a single large airline order can spike the series by a substantial margin one month, only for the category to give it all back the next. The three-month average, which smooths that noise, rose 0.5% month-on-month and 9.3% year-over-year, rates that look considerably less sanguine once you consider where the demand is originating.
The year-over-year jump of 8.5% in total durable goods orders is worth noting, but core capital goods orders at 14.1% annual growth is the number the AI infrastructure narrative is actually resting on. And there is a specific mechanism here, not just a generalised boom.
Core Capital Goods Orders and the AI Infrastructure Machine
Break the category into its components and the AI infrastructure build-out is not a background theme, it is the dominant signal. Machinery orders, which cover engine and turbine equipment, ventilation, heating, air-conditioning, and commercial refrigeration alongside construction and industrial machinery, spiked 1.1% month-on-month and 15.1% year-over-year to $45.5 billion. Data centre construction requires all of these: gas-turbine and diesel generators, cooling systems, and the heavy equipment to put the buildings up. Reports of persistent shortages in turbine blades and vanes suggest the order backlog is not clearing quickly.
Computer and electronic products orders were flat month-on-month at $31 billion, though tEDmag noted computers and related products increased 1.5% in August. The year-over-year figure of 16.5% is the one that matters: this category includes US-located semiconductor fabrication, and the numbers reflect sustained demand that is not being met overnight. Electrical equipment, appliances, and components (covering the switchgear, transformers, and related kit that data centres require) rose 1.1% month-on-month and 7.6% year-over-year to $19 billion. Fabricated metal products pulled back 0.6% from July’s record but remained 8.6% higher year-over-year at $45 billion.
The critical context that the growth-story framing tends to underweight is the backlog itself. Unfilled orders for manufactured durable goods increased $5.0 billion, or 0.4%, to $1,391.4 billion in August, per the Census Bureau’s advance data. That is not a sign of demand running ahead of capacity in a healthy, self-correcting way. It is a sign that supply chains are absorbing orders faster than they can produce output, which is precisely the condition that pushes input costs upward and keeps them there.
The Inflation Undertow the Orders Data Carries
This is where the consensus may be overweighting the positive read. Strong core capital goods orders are treated as a straightforward indicator of future economic activity, which they are. But they are also an early indicator of pricing pressure working its way through the production chain. S&P Global‘s US Composite Flash PMI for September, released alongside this data cycle, put the situation plainly: US business output was growing at its fastest rate in over five years, but supply chain bottlenecks were among the most severe in the survey’s near-two-decade history outside the pandemic period. Backlogs of work were rising sharply. Firms’ input costs jumped in September at the steepest rate in four years, with fuel and transport costs adding to upward pressure on selling prices.
S&P described the accumulation of uncompleted orders as positive for future output and capacity expansion, and then immediately flagged it as “a worry for the inflation outlook.” That qualifier tends to get dropped in coverage that leads with the orders surge. The two readings are not separable: the same constraint that makes core capital goods orders look strong is the one generating pricing power at the producer level and feeding it forward.
Orders, by definition, are a lead indicator. The Census Bureau’s own data shows that it may take months before orders clear the backlog and convert into actual production and sales. With unfilled orders sitting at $1,391.4 billion and input costs accelerating through September, the question is not whether the AI infrastructure boom is real (it clearly is) but whether the inflation the build-out is generating has been adequately priced into rate expectations.
