Skip to content
Contact us

AXIOMA ROOF™ SCORE HIGHLIGHTS

WEEK OF SEPTEMBER 28, 2026

Insights from last week's changes in investor sentiment:

Cap-weighting is but imperialism in financial markets. The bigger you become, the more capital you command; the more capital you command, the bigger you become. Over the past few years, that logic has turned technology from a mere province of the market into its imperial capital, with AI installed as king and the rest of the sectors serving as its court.

Yet concentration is not the only way systems lose sight of their original purpose. Self-reinforcing dynamics have a habit of taking on a life of their own. What begins as a means to an end can gradually become an end in itself. Capital behaves this way. Governments do too.

The means we choose often dictate the ends we achieve. The problem with wars of choice is that, eventually, the means become the ends. The U.S. went to war with Iran to prevent it from acquiring  nuclear weapons. Seven months later, the nuclear issue remains unresolved, while an oil shock, an affordability crisis and falling approval ratings have been added to the original problem. The US President is now telling the UN that he may have to "annihilate" the Islamic Republic to bring the war to an end; hardly the language of a clean exit, and a rather good illustration of means becoming ends.

Which raises the next question, one that has been attracting rather more attention lately: will US voters add to the problem in November? And if they do, will the same logic apply there too? The administration is already laying the groundwork for a broader use of "national security" as a justification for executive power, from barring three news organizations from the White House to seeking greater federal control over election administration and voter rolls.

All of this may matter rather more to investors than equity markets currently suggest. The S&P 500 reached another record high, propelled by the AI cult. Bond investors, meanwhile, appear to be focused on a rather different story. Equity investors continue to price the self-reinforcing logic of AI dominance; bond investors are increasingly pricing the self-reinforcing consequences of everything else.

Over the past month, the dominant story across our ten (equity) markets has been the steady rehabilitation of investors' willingness to take risk. Aggregate sentiment has improved from slightly negative a month ago to roughly balanced today. Yet the past week itself, despite a UN General Assembly and a third Trump-Xi meeting that supplied no shortage of headlines, contributed very little to that journey. The monthly improvement remains intact, but the latest weekly move sits comfortably inside the noise band.

The more interesting development is not where sentiment sits, but how uniformly investors have arrived there. One month ago, cross-market dispersion stood around the 61st percentile of its historical range. Today it sits at the 1st percentile. Not merely low. Compressed almost beyond recognition. Investors across regions, sectors and economic circumstances are increasingly expressing variations of the same opinion, even if they disagree on the details. When dispersion collapses to this extent, local stories lose their voting rights and the macro backdrop acquires a majority government. That does not mean everyone is optimistic. It means everyone is listening to the same soundtrack.

The monthly regime migration tells a similar story. A month ago, five of the ten markets we track sat in either Negative or Bearish territory. Today only one remains there. Three markets have climbed out of risk-off territory without a corresponding increase in outright optimism: the number of Bullish and Positive markets is unchanged, while the number of Negative and Bearish readings has fallen from five to two. Investors have not embraced risk so much as backed away from avoiding it. There is a difference. Confidence tends to announce its arrival; anxiety prefers a quieter exit.

Japan remains the clearest example of the month's shift in mood. Sentiment among Japanese investors improved by more than one full ROOF point over the past month and strengthened further over the past week, the only market where the weekly and monthly trends remain fully aligned. China offers a different lesson. Sentiment there improved materially over the month as well, yet remains negative at -0.48, just above the bearish threshold. That improvement deserves recognition without over-celebration. Investors can spend weeks climbing out of a hole only to discover they are still underground.

Elsewhere, the pattern is one of hesitation rather than conviction. Sentiment among U.S. investors remains positive at +0.25 after a material monthly improvement, but was little changed over the past week despite equity indices continuing their ascent. Investors in APAC ex-Japan tell a similar story: sentiment remains firmly positive following a substantial monthly improvement, while the latest week produced little additional progress. Investors seem content to keep buying, but less eager to increase the size of their bets.

That distinction matters because sentiment predicts behavior rather than returns. When risk tolerance and risk aversion sit in rough balance, investors become selective consumers of information. Good news receives polite attention. Bad news receives cross-examination. The aggregate ROOF score now sits in Neutral territory, which offers less comfort than the label implies because it describes balance, not agreement. A tied vote is still a disagreement.

The coming week offers investors no shortage of material with which to justify whichever view they already hold. U.S. payrolls, ISM surveys, income and spending data, and another inflation reading arrive against a Federal Reserve that still regards the labor market as being near full employment. European investors will receive inflation and unemployment figures while trying to judge how much further the ECB may yet have to travel. China gets another reading on manufacturing activity in a shortened week, while Japan publishes industrial production, retail sales and the latest Tankan survey. There will be plenty of facts. The question is whether any of them meaningfully alter the balance between risk tolerance and risk aversion. After a month in which investor sentiment improved while becoming almost perfectly synchronized across regions, confirmation bias may be easier to find than confirmation itself. When everybody starts reading from the same script, even surprises begin to sound like rehearsals.

Aggregate ROOF Trend: The black line is the aggregate mean of ROOF scores across the ten markets; the shaded grey band shows the range from the most bearish to the most bullish market on each day, indicating the dispersion of sentiment across the universe. Reading it: a rising line indicates increasing risk tolerance; a declining line indicates increasing risk aversion. 

Bottom strip: cross-market dispersion percentile — the cross-sectional standard deviation of ROOF across the ten markets, percentile-ranked against its own full history. Shaded zones mark elevated (>80th percentile) and compressed (<20th) readings. Reading it: a spike into the top shaded zone is a material divergence episode (sentiment moving in different directions across markets), a slide into the bottom shaded zone is a material convergence episode on a common driver (sentiment moving in the same direction across markets). 

Regime Distribution: Three horizontal stacked bars show how the ten markets are distributed across the five regimes — today, one week ago, and one month ago. Each bar is colored by regime: red (Bearish), yellow (Negative), grey (Neutral), blue (Positive), green (Bullish). The white vertical marker on each bar shows the aggregate ROOF score for that period. Tick marks below the bars align with the regime thresholds at ±0.20 and ±0.50. Reading it: a leftward shift over time indicates broadening deterioration; a rightward shift indicates broadening improvement. Widening tails signal rising dispersion.

Market Monitor: A table showing, for each market: current ROOF score, current regime, weekly and monthly changes, regime one month ago, and distance to the nearest extreme threshold. Color cues highlight regime deteriorations (red) and improvements (green). Reading it: scan the "1M Ago Regime" column for markets that have crossed regime bands over the past month; check the "Distance" column to find markets close to the ±0.50 extreme thresholds.

Correlation Matrix (Δ1M): A heatmap of correlations between monthly sentiment changes across all market pairs, over a rolling 60-day window. Green cells indicate that investor sentiment in the two markets changed in the same direction; red cells indicate opposite directions. The rightmost column shows each market's average correlation with the rest of the universe. Important: these are correlations of sentiment changes, not market returns or ROOF levels. High correlation means investor mood in the two markets moved in sync over the past 60 days.

You may also like

  • Privacy policy
  • Cookie Policy
  • Terms of Use
  • Trademark guidelines

Copyright © 2026 SimCorp A/S