Macro Monthly Report — September 2026

Executive Summary

Three of the four central banks in this report raised rates in September, and the one that did not is out of room. The Fed lifted its benchmark by 25 bp to 3.75–4.00%, unanimously and for the first time since 2023; the ECB took the deposit rate to 2.50%; the BoJ went to 1.25% on a 7–2 vote. The SNB held at 0% for a fifth meeting and shifted its guidance back toward FX intervention, which is what a central bank does when the policy rate has nowhere to go. The common cause is energy. US headline CPI stood at 3.4% y/y in August with energy up 16.3%; euro area HICP rose to 3.3% with energy at 14.3%; Swiss petroleum product prices climbed 25.2%. In all three cases core is materially lower, 2.4% in the US and the euro area, so this remains a supply shock rather than a demand problem, which is precisely what makes it awkward to tighten into.

What has changed since August is that the shock is no longer expected to resolve quickly. Brent closed at $104.45, up 22.2% on the month and roughly +72% from the 1 January close. Iran tabled a proposal at the UN that would reopen Hormuz within seven days; the WSJ reports Trump has rejected it and privately expects to resume bombing after the November midterms. The asking price, blockade lifted, funds released, sanctions waived, no nuclear concessions, explains the rejection. Meanwhile the underlying economy has not cracked: the US flash composite PMI rose to 58.4, the steepest rise in private-sector output since July 2021, and while headline Q2 GDP moderated to 1.5% annualised, real final sales to private domestic purchasers grew 4.2%. The AI investment cycle is doing enough work to let the Fed tighten into an energy shock without breaking growth, which is an unusual and probably temporary luxury.

The dominant risk sits in the Treasury market and runs through Tokyo. The 10y closed at 5.17%, 53 bp higher on the month and the highest since July 2007, with the move driven by term premium rather than policy expectations; it happened almost entirely before the Fed acted, and the post-hike relief was around 5 bp. At that level the 2027 corporate refinancing wall and the servicing cost on a $40 trillion debt stock stop being forward-looking concerns. Japan is the amplifier: as the largest foreign holder of Treasuries at over $1.2 trillion, further yen weakness would push Tokyo toward selling US paper to fund intervention, after the $96.5 bn already deployed in July and the first coordinated US–Japan action since 1998. Against all of this the S&P 500 closed at a record 7,743.41 with the VIX at 14.21. That combination prices a specific chain, margins absorb the energy pass-through, the discount rate stops here, the Fed is nearly done, at close to certainty. The chain may hold. It is not priced as a probability.

Key Takeaways

• Synchronised tightening: Fed +25 bp to 3.75–4.00% (unanimous, first hike since 2023), ECB +25 bp to 2.50% deposit, BoJ +25 bp to 1.25% (7–2). SNB held at 0% and shifted to FX intervention guidance.
• Energy, not demand: US CPI 3.4% y/y with energy +16.3%; euro area HICP 3.3% with energy +14.3%. Core at 2.4% in both. A supply shock that central banks are tightening into.
• Treasuries at 2007 levels: 10y at 5.17%, +53 bp on the month, driven by term premium rather than policy expectations. The post-hike relief was about 5 bp before yields resumed rising.
• Oil is gap risk, not a trend: Brent $104.45, +22.2% MoM. Iran's UN proposal would reopen Hormuz within seven days; Trump has reportedly rejected it and expects to escalate after the midterms.
• Japan is the amplifier: Holding over $1.2 trn in Treasuries after $96.5 bn of July intervention, Tokyo is the channel through which yen weakness transmits into US yields.
• Markets price none of it: S&P 500 at a record 7,743.41 with the VIX at 14.21, near the bottom of its multi-year range.

Market Sentiment & Asset Overview

The Treasury market is where the period's real damage sits. The 10y closed at 5.17%, 53 bp above where it stood in August and the highest since July 2007. Two things are worth separating. The move up happened almost entirely before the Fed acted, driven by term premium rather than by expectations of policy: investors demanding compensation for holding duration into a supply-shock inflation that no longer looks transitory. The move back down after the hike was small, on the order of 5 bp. Two days afterwards yields began to rise again and are now at their highest. 5.17% is so high that it acts as a major limit on the economy. At this level, everyone borrowing money feels the pressure. Companies with large loans coming due in 2027 face a sharp jump in interest costs when they renew their debt. Investors and credit markets face much higher financing costs for debt products tied to government interest rates, making heavily indebted business strategies unprofitable. At the same time, the government itself must pay far more interest on its national debt, straining public budgets and forcing tough decisions on spending and taxes.

Brent at $104.45, up 22.2% on the month and roughly +72% from the 1 January close of $60.75, is the mechanism underneath all of the above. Seven months into the war, the position is binary rather than gradual. Iran tabled a proposal at the UN, routed through Qatari mediators, that would reopen Hormuz within seven days and pause fighting on all fronts; the WSJ reports Trump has rejected it and privately expects to resume bombing after the November midterms. The asking price explains the rejection: Tehran wants the blockade lifted, frozen funds released and sanctions waived, while conceding nothing on its nuclear programme. Supply has meanwhile worsened on a second front, with the Houthi blockade putting the Red Sea alternative route at risk while Hormuz stays closed. Demand has not broken: Chinese refinery throughput rose in August, so the largest net importer is absorbing $100+ crude rather than rationing it. The practical consequence is that the risk premium is now gap risk in both directions. A deal reopens a fifth of seaborne flow inside a week; a post-midterm escalation extends the closure through winter. $104 is the market splitting the difference.

Against all of this, equities and volatility are pricing a different world. The S&P 500 closed at 7,743.41, up 0.88% on the month and roughly +13% year to date, while the VIX sits at 14.21 near the bottom of its multi-year range. An index at records with the 10y at 5.17% and Brent up 22% in a month is not an impossible combination, but it requires a specific chain of assumptions to hold: that margins absorb the energy pass-through, that the discount rate stops rising here, and that the Fed is finished after one or two moves. A VIX at 14 prices that chain close to certainty.

Changes are between 25 August and 25 September. Sources for table and text above: FRED (Federal Reserve Bank of St. Louis), Reuters, Investing.com, Yahoo Finance, Wall Street Journal.

Business Cycle Positioning

The global economy is overall surprisingly resilient, mainly driven by a strong global AI investment cycle and rising military spending, although geopolitical tensions and energy price shocks make the picture vary regionally.

The US flash composite PMI rose to 58.4 from 56.0 in August, with manufacturing at 56.7 and services at 58.7, the steepest rise in private-sector output since July 2021. Headline Q2 GDP growth moderated to 1.5% annualised, but real final sales to private domestic purchasers grew 4.2%. Full-year 2026 growth is projected at 2.3%, driven by AI infrastructure investment, equipment spending and private consumption.

Switzerland posted the strongest manufacturing reading of the group. The procure.ch–UBS Manufacturing PMI rose 3.9 points to 57.1 in August, a sixth consecutive month above 50, with production at 59.8, order books at 57.5 and purchasing volumes at 61.0. Services stood at 58.3. Q2 GDP was strong, helped by an unusually robust pharmaceuticals contribution. Full-year growth is projected at 1.5–2.0%, with unemployment at 3.0% in August and the policy rate unchanged at 0%.

China's manufacturing PMI stayed in contraction at 49.1. Q2 GDP growth slowed to 4.3% y/y. High-tech manufacturing grew 16.7% and exports 14.6%, but fixed-asset investment contracted 7.2% and retail sales grew just 0.4% y/y in August. Emerging markets diverged. Taiwan, South Korea, Malaysia and India are expanding on semiconductor capacity utilisation and AI infrastructure demand, with 74% of surveyed chief economists expecting strong growth in India and 73% in Southeast Asia. Energy-importing and non-tech emerging markets face margin compression and tighter financial conditions from elevated energy costs and shipping disruption.

Central Bank Policy Monitor

What Changed This Month

Federal Reserve (Fed) — The Federal Reserve voted unanimously to raise its benchmark interest rate by a quarter of a percentage point to a range between 3.75% and 4.00%, marking its first rate hike since 2023. Driven by persistent inflation from tariffs, AI infrastructure buildouts, and rising energy costs from the Middle East conflict, the Federal Open Market Committee noted in its statement: "Today's policy action will support a timelier return" to its 2% target, emphasizing that "Inflation remains elevated" and asserting that "The committee will deliver price stability". (Source: Federal Reserve / FOMC Statement, Yahoo Finance)

European Central Bank (ECB) — The European Central Bank raised all three key interest rates by 25 basis points, bringing the deposit facility rate to 2.50%. Reconciling the decision with upward revisions to its medium-term inflation projections, the Governing Council stated in its monetary policy statement: "The conflict in the Middle East continues to generate inflation pressures, and inflation is set to remain well above target for an extended period". Markets are expecting further hikes but Lagarde declined to give clear guidance, saying the outlook was too unclear to plot a path ahead. But the ECB raised its growth forecasts for this year to 0.9% and for next year to 1.4%, underlining that the eurozone economy has withstood the Middle East war energy shock better than feared. (Source: ECB Economic Bulletin, Le Monde)

Swiss National Bank (SNB) — While the Swiss National Bank kept its policy interest rate unchanged at 0% for the fifth consecutive meeting, it adjusted its forward guidance on currency interventions and revised its conditional inflation forecast upward through 2028. Shifting back to its standard intervention language after dropping prior phrasing focused on safe-haven pressure, Chairman Martin Schlegel stated in the official monetary policy assessment: "We are also willing to be active in the foreign exchange market as necessary to ensure appropriate monetary conditions." (Source: Swiss National Bank)

Bank of Japan (BoJ) — The Bank of Japan raised its uncollateralized overnight call rate by 25 basis points to around 1.25% in a 7–2 vote, accelerating its rate hike cycle. Pointing to rising inflation expectations and firm corporate pricing power, the Policy Board stated in its official release: "The Bank will encourage the uncollateralized overnight call rate to remain at around 1.25 percent", while reaffirming that it "will continue to raise the policy interest rate and adjust the degree of monetary accommodation" in response to economic developments. (Source: Bank of Japan)

Regional Overviews

United States

Growth — The US economic expansion remains resilient, driven by robust private domestic demand and a powerful technology investment cycle. While headline annualized real GDP growth moderated to 1.5% in Q2 2026 (down from 2.1% in Q1), real final sales to private domestic purchasers expanded by a strong 4.2%, underpinning a full-year 2026 GDP forecast of 2.3%. Growth is anchored by private consumption, defense manufacturing orders, and heavy capital expenditure in artificial intelligence infrastructure, networking equipment, and data centers.

Inflation — Price pressures remain elevated and sticky above the Federal Reserve's 2% target. In August 2026, headline CPI inflation stood at 3.4% year-on-year, while core CPI inflation eased to 2.4%. Energy prices surged 16.3% year-on-year, with Middle East conflict disruptions driving US diesel prices to record highs of $5.58 per gallon, and import duties on petrochemicals, metals, and manufactured goods continue to add direct input cost pressures across manufacturing and retail.

Key Risk / Watch — Monetary Policy Friction: The Federal Reserve unanimously raised its benchmark rate by 25 bps to 3.75%–4.00% (its first hike since 2023). With 16 of 18 FOMC members projecting further tightening this year, the Fed faces sharp political pushback from the White House calling for rates below 1%. Sovereign Debt Burden & Yield Spikes: The 10-year Treasury yield pushed above 5.0% and 30-year yields reached 5.47%, driven by persistent inflation risks and a record $40 trillion US national debt. Geopolitical Energy Shocks: Transit disruptions in the Strait of Hormuz present ongoing upside risks to crude oil, freight, and supply chains.

Eurozone

Growth — The Eurozone economy demonstrated unexpected resilience in Q2 2026, expanding by 0.6% quarter-on-quarter (0.3% excluding volatile Irish GDP data). The European Central Bank (ECB) revised its full-year 2026 real GDP growth forecast upward to 0.9%, followed by 1.4% in 2027. Expansion is primarily supported by resilient private consumption, expanding digital services, and a substantial rise in public infrastructure and defense spending, where cumulative national defense investments are projected to add 0.4 percentage points to GDP growth over 2025–2028.

Inflation — Inflationary pressures re-accelerated in late summer, with headline HICP inflation rising to 3.3% year-on-year in August 2026 (up from 2.9% in July). In contrast, core inflation edged down slightly to 2.4% from 2.5% in July. Energy Price Surge: Energy inflation soared to 14.3% year-on-year in August (up from 10.3% in July), driven by escalating Middle East conflict tensions, elevated liquid fuel refining margins, and a 62% surge in European gas prices. Non-Energy Industrial Goods (NEIG): Goods inflation picked up to 1.2% in August (from 0.9% in July), reflecting rising manufacturing input costs.

Key Risk / Watch — Geopolitical Energy Shocks & Second-Round Effects: Ongoing conflict in the Middle East and Russia's war against Ukraine pose persistent upside risks to natural gas and crude oil prices, threatening to trigger broader second-round inflationary effects across goods and services. ECB Policy Path & Financial Conditions: On 10 September 2026, the ECB raised its key deposit facility rate by 25 bps to 2.50% (main refinancing to 2.65%) while maintaining a meeting-by-meeting, data-dependent stance without pre-committing to future rate paths. Fiscal Deficits & Defense Expansion: The Eurozone fiscal deficit is projected to widen to 3.6% of GDP in 2026 (debt nearing 90% of GDP in 2028) as governments expand defense spending under activated EU escape clauses, leaving several member states under Excessive Deficit Procedures.

Switzerland

Growth — The Swiss economy exhibits solid expansion, supported by strong second-quarter performance and broad-based underlying demand. While Q2 GDP growth was exceptionally strong due to a temporary surge in the pharmaceutical sector, non-pharmaceutical output remained firm. The Swiss National Bank (SNB) revised its full-year 2026 real GDP growth forecast upward to between 1.5% and 2.0% (with SECO forecasting 1.7%), expecting growth to normalize to around 1.5% in 2027. Activity is underpinned by stable domestic consumption and solid export demand, while the unemployment rate remained low and steady at 3.0% in August.

Inflation — Swiss consumer price inflation remains exceptionally low by global standards and well within the SNB's 0% to 2% price stability target. Headline CPI inflation rose slightly to 0.8% year-on-year in August 2026 (up from 0.6% in May), while core inflation remains subdued. The SNB projects average annual headline inflation at 0.7% in 2026 and 0.8% in both 2027 and 2028, with a temporary peak at 1.2% in Q4 2026. Energy & Petroleum Products: Petroleum product prices surged 25.2% year-on-year in August, serving as the primary driver behind the headline CPI increase. Imported Goods & Currency Effects: A 3% trade-weighted depreciation of the Swiss franc increased import prices for raw materials, plastics, and electronic components.

Key Risk / Watch — FX Guidance: The SNB updated its foreign exchange stance to state it is "willing to be active in the foreign exchange market as necessary", so the EUR/CHF trajectory is important to watch.

Japan

Growth — The Japanese economy continues a moderate recovery, with real GDP expanding by 0.3% quarter-on-quarter in Q2 2026 (1.1%–1.4% annualized). Full-year 2026 real GDP growth is projected at 0.6%, as elevated energy import costs temporarily weigh on economic activity. Domestic momentum is supported by high corporate profits, picking-up business fixed investment, and a tight labor market with unemployment holding low at 2%–2.5%.

Inflation — Inflationary pressures are steadily broadening as corporate pricing behavior shifts toward passing through rising labor and input costs. CPI inflation (all items less fresh food) stands in the 1.5%–2.0% range and is projected to accelerate clearly above 2.0% in H2 FY2026, while corporate goods price growth has exceeded 7% year-on-year for three consecutive months.

Key Risk / Watch — BoJ Tightening & Political Resistance: The Bank of Japan raised its policy rate by 25 bps to 1.25% in September 2026 (7–2 vote), accelerating its rate hike cycle. However, dissenting board votes (Asada and Sato) and political preferences for easing highlight growing pushback against aggressive future hikes. Yen Carry Trade Unwind & Repatriation: Narrowing rate differentials against the US Fed (3.75%–4.00%) threaten to unwind global yen carry trades. Meanwhile, rising 10-year JGB yields (approaching 3.0%) increase incentives for Japanese institutional investors to repatriate capital from foreign bond markets. FX Volatility & Intervention Burdens: After the yen touched nearly 40-year lows near ¥163.73/$, joint US-Japan market action and a record $96.5 billion (¥15.4 trillion) in Japanese interventions were required to stabilize the currency around ¥159.5/$.

China

Growth — China's economic expansion remains highly asymmetric, balancing a buoyant high-tech export engine against severe domestic demand headwinds. Real GDP growth slowed to 4.3% year-on-year in Q2 2026 (down from 5.0% in Q1). Growth is anchored by strong industrial production, which expanded 5.2% year-on-year in August. However, overall momentum is severely constrained by sluggish private consumption, with retail sales growing by just 0.4% year-on-year in August, and a sharp contraction in total fixed-asset investment (-7.2% in Jan–Aug).

Inflation — Consumer price inflation in China remains subdued due to persistent domestic economic slack and weak household demand. In August 2026, headline CPI inflation rose mildly to 0.8% year-on-year (up from 0.5% in July), while core CPI inflation (excluding food and energy) stood at 1.0%. Meanwhile, industrial PPI inflation picked up to 3.8% year-on-year.

Key Risk / Watch — Deepening Real Estate Downturn: Real estate development investment contracted by 19.9% year-on-year in the first eight months of 2026, with commercial building sales value down 13.0%, continuing to drag down household wealth, consumer confidence, and local government revenues. Supply-Demand Imbalance: A pronounced structural imbalance persists between strong state-supported industrial supply (+16.7% in high-tech) and weak domestic household absorption (+0.4% in retail sales). Geoeconomic Friction & Trade Barriers: Intensifying trade tensions and tariff scrutiny from the US and Europe (amid concerns over "China shock 2.0" industrial competition) threaten export momentum, while foreign direct investment into China remains depressed.

Emerging Markets

Growth — Strong expansion across Asian hubs (India, Vietnam, Malaysia), powered by booming global AI infrastructure and semiconductor demand. But there is big regional divergence: high growth expectations for South and Southeast Asia, whereas Latin America and the Middle East lag due to oil production caps and geopolitical friction.

Key Risk / Watch — Tightening Global Liquidity & Currency Depreciation: The combination of Federal Reserve rate hikes and rising 10-year US Treasury yields above 5.0% keeps global borrowing costs elevated. This tight financial backdrop creates persistent currency depreciation pressure across EM FX, increasing external debt-servicing burdens and import price pass-through.

Special Focus: Japan's Monetary Pivot and the Global Significance of the Yen

The Yen's Historic Slide and the Interest Rate Gap

For years, the Japanese yen experienced a sustained downward trend driven by a stark interest rate divergence between the Bank of Japan and other central banks. While other central banks have far higher key interest rates, the BoJ maintained ultra-loose monetary settings, pushing the yen to a nearly four-decade low of ¥163.73 per US dollar in late July 2026. This widening yield differential fueled massive global carry trades, where international investors borrowed cheap yen to fund higher-yielding assets worldwide, while severely exacerbating imported inflation pressures within Japan.

The Historic Coordinated US-Japan Intervention

To halt the currency's decline, the United States and Japan executed a joint currency intervention on 31 July 2026, marking the first coordinated US-Japan market action since 1998. In an extraordinary move to directly support the yen, the Federal Reserve Bank of New York sold euros to purchase yen on behalf of the US Treasury, operating alongside Japan's own operations of selling US dollars for yen. This joint intervention successfully engineered a sharp 4.6% rebound, lifting the yen from ¥163.73 back to approximately ¥156.12 against the dollar in just a few days.

Why Washington Stepped In: Treasuries and US Credit Markets

Washington's decision to actively buy yen highlights how a weakening Japanese currency poses a direct threat to US financial stability. As the world's largest foreign holder of US Treasury bonds, holding over $1.2 trillion as of April 2026, Japan faced pressure to sell US Treasuries to raise the dollars required for unilateral currency interventions. Had Japan been forced into large-scale Treasury sell-offs, US bond yields would have spiked, raising borrowing costs across the American economy. By deploying US financial power to buy yen directly, Washington stabilized US credit conditions and prevented disruptive spillovers into its domestic debt market.

BoJ Policy Normalization and the Carry Trade Unwind

Compounding this intervention dynamic, the Bank of Japan has embarked on a policy normalization path, raising its policy interest rate to 1.0% and subsequently to 1.25% in September 2026. As domestic Japanese yields rise and make home-market investments relatively more attractive, the narrowing rate differential threatens to unwind decades of yen carry trades. A structural repatriation of Japanese capital back into domestic assets risks withdrawing liquidity from foreign debt and equity markets, establishing the USD/JPY exchange rate as a critical barometer for global systemic stability.

Outlook & Key Risks

Base Case — No settlement before the November midterms and no major escalation. Hormuz stays closed and Brent holds $95–115. The Fed delivers one more 25 bp move to 4.00–4.25% by December, in line with 16 of 18 FOMC members projecting further tightening. The BoJ continues normalising toward 1.50%, which supports the yen without forcing Tokyo into large-scale Treasury sales. The 10y UST stays in 5.00–5.40%, the S&P 500 flat to −5%, USD/JPY in 155–162 with intervention on approaches to 163.

Upside Risks — Washington accepts a version of the Iranian proposal. Because the deal carries a seven-day countdown, this arrives as a gap: Hormuz reopens, Brent falls to $70–82, and the energy contribution that drove US CPI energy +16.3% reverses within two prints. The Fed stops at 3.75–4.00%, the 10y UST falls to 4.30–4.60%, and the S&P 500 gains 5–10% on the discount rate alone. A narrower US–Japan differential removes the pressure on the yen that made July's intervention necessary.

Downside Risks — The rejection hardens into the post-midterm bombing campaign the WSJ reports Trump expects. Brent moves to $130+, US headline CPI breaches 4%, and the Fed is forced into 50 bp rather than 25. The 10y UST breaks above 5.75%, at which point the 2027 refinancing wall and the $40 trillion debt burden stop being forward-looking risks. Japan is the transmission channel: renewed yen weakness alongside rising US yields would push Tokyo toward selling Treasuries to fund further intervention (the $96.5 bn already deployed in July is the reference point), which pushes US yields higher still. The S&P 500 corrects 15–25% from a starting VIX of 14.21.

Key Dates & Events

Prepared by Michele Brun · Investment Club Zurich — Macro Team · Published 29 September 2026 · Data as of 26 September 2026 · Sources: Federal Reserve, ECB, Eurostat, SNB, PBC, Bank of Japan, Japan Statistics Bureau, Japan MOF, US Treasury TIC, S&P Global, BIS, WEF, FRED / St. Louis Fed.