UBS: US Tech Volatility Returns to Bubble Levels, Defensive Sectors Outperform

According to Chaoshang Research, UBS's research report dated September 21, 2026 indicates that the median 3-month rolling realized volatility for US-listed semiconductors reached 0.69, the technology sector stood at 0.5, software & services at 0.4, and financials at just 0.17. The share of total US capital expenditures accounted for by hyperscalers rose from less than 5% in 2015 to an estimated over 30% in 2026, increasing the risk of dilution to cash flow return on investment (CFROI). UBS identified US-listed equities with a fixed charge coverage ratio below 1x, including Alphabet, Microsoft, Amazon, SpaceX, Tesla, and Oracle.