Government shutdown and Iran tensions spark a defensive rout

The US government shutdown that began October 1 is heading into its second week with no resolution in sight, and it is already the dominant force behind last week's sector rotation. After President Trump waved off a fresh round of Iran peace talks on September 28, Brent crude jumped toward 110 dollars a barrel and Treasury yields climbed, triggering a flight out of rate-sensitive and defensive sectors. Financials, health care, communication services, materials, consumer staples and real estate all fell more than 1.8 percent on the week, while Energy and Information Technology were the only sectors that advanced. The Nasdaq-100 held onto a 0.68 percent gain even as the S&P 500 slipped 0.22 percent, underscoring how narrow the week's leadership was.

This week, the shutdown's practical effect shows up as a data vacuum: the September jobs report has already been delayed past its normal release date, and Wednesday brings the minutes from the Fed's September policy meeting, the clearest written record investors have of committee thinking until official data resumes. With CPI and retail sales now at risk of delay next week, markets have fewer anchors than usual heading into bank earnings season, which opens October 13.

Against that backdrop, this week's earnings calendar is thin but informative. PepsiCo reports Thursday with the first real read on consumer-staples demand and input costs since the sector's rough week, and Delta Air Lines reports Friday with an early look at travel demand and fuel costs while oil remains elevated. Neither name moves the market alone, but both will be parsed closely for signs of whether last week's defensive-sector weakness reflects genuine demand softness or simply a rotation into energy and AI-linked technology.

Technology (XLK +1.80%) was the only sector besides Energy to post a gain last week, and the Nasdaq-100's 0.68% advance against a down S&P 500 shows how narrow the rally has become. Micron (MU) beat EPS estimates by 2.6% last week, reinforcing the memory-pricing upcycle that has become a pillar of the AI trade, and our catalyst radar flagged unusual options activity in Nvidia (NVDA), AMD and Broadcom (AVGO) heading into this week. AMD also disclosed an equity offering, a reminder that even the best-performing names in this group are still raising capital to fund AI infrastructure buildout rather than funding it purely from cash flow. Several mega-cap technology names also showed up on our catalyst radar for unusual option volume, alongside flags tied to disclosed trading activity around them. For a market that is otherwise short on hard economic data this week, these semiconductor and mega-cap names remain the most liquid proxy for how investors are pricing the AI capital-spending cycle, and their relative strength against a weak broad tape is the clearest standing trend coming out of last week.

Energy (XLE +1.26%) was last week's second-best sector after President Trump waved off a new round of Iran peace talks on September 28, pushing Brent crude toward 110 dollars a barrel and lifting natural gas alongside it (+1.7% on the week, +4.8% over the month). Copper added a more modest 0.8%, consistent with a broad commodity bid rather than an oil-specific spike. What stands out is the divergence inside the metals complex: gold rose just 0.4% on the week and is down 7.8% over the month, while silver gained 0.8% on the week but is off 7.9% over the month, a pattern that looks more like a commodity and inflation story than classic safe-haven demand. Inside our tracked universe, the energy-adjacent names on the catalyst radar cut both ways: CenterPoint Energy (CNP) disclosed both a congressional stock trade and an equity offering, while Uranium Energy (UEC) missed EPS estimates by more than 100% last week even as fuel markets tightened. The sector's next real test is whether Brent holds its gains as the shutdown drags on.

Health Care (XLV -2.65%) was the weakest S&P sector last week, and our catalyst radar shows why the group carries elevated event risk right now. BioNTech (BNTX) has three separate phase 3 readouts flagged: pumitamig (BNT327) in first-line triple-negative breast cancer in China, gotistobart in second-line-plus squamous non-small-cell lung cancer, and BNT113 in first-line HPV16-positive, PD-L1-positive head and neck cancer. Summit Therapeutics (SMMT) is sitting on a phase 3 overall-survival readout for ivonescimab in non-small-cell lung cancer from its Harmoni program, and also disclosed an equity offering, a combination that tends to add volatility on top of trial-outcome risk. None of these readouts are confirmed for this specific week, but they explain why health care's decline looks more concentrated than a simple rotation out of defensives: a cluster of binary oncology outcomes sits on top of a sector already being sold for rate and positioning reasons.

The government shutdown enters its second week with no funding deal in place, keeping several federal data releases delayed or at risk, including catch-up timing tied to the September jobs report. The one fixed point on the macro calendar is Wednesday, when the Fed releases minutes from its September policy meeting, the clearest written signal of committee thinking available until official data resumes. CPI and retail sales, normally due the following week, are also at risk of delay depending on how long the shutdown lasts. On earnings, Monday brings McCormick (MKC), Tuesday adds Constellation Brands (STZ) and Lamb Weston (LW), and Wednesday includes Applied Digital (APLD) and Levi Strauss (LEVI). The two highest-signal reports land late in the week: PepsiCo (PEP) on Thursday, the first consumer-staples read since last week's sector decline, and Delta Air Lines (DAL) on Friday, an early look at travel demand and fuel costs with oil still elevated. Bank earnings season opens the following week on October 13.