Scenarios
Bear case first, in full. The bear case carries the largest non-base weight at 35% because the data has shifted: breadth is narrowing, earnings revisions turned negative, and the curve is steepening on real-rate stress rather than disinflation. The bull case is internally coherent but requires a coordinated revisions inflection that the data does not yet show.
Three scenarios
Bear case
Probability 35% · fair value 4,480
Bear-led curve steepening continues; Q3 revisions deepen; mega-cap multiple compression triggers index drawdown to 4,300–4,600.
Drivers
- 10y real yield breaks above 2.6% and stays there for two months.
- Q3 cap-weighted earnings revision turns more negative; Industrials and Materials lead.
- Mega-cap leadership cracks; equal-weight participation does not pick up the slack.
- Credit spreads widen 50+ bps; HY OAS breaks 450 bps.
Kill switches
- Fed signals a real-rate cap or curve-control posture.
- Q3 revisions stabilise above flat by July.
Base case
Probability 45% · fair value 5,065
Sideways-with-downward-bias; index oscillates 4,900–5,250 as breadth churns; defensive sectors compound while leadership works through correction.
Drivers
- Yield curve normalises slowly; long-end real rates plateau between 2.0% and 2.5%.
- Earnings revisions stabilise but do not re-accelerate; growth is positive but unimpressive.
- Defensive tilt (Healthcare, Staples, Utilities) compounds quietly while Technology corrects laterally.
- Credit spreads stable; no stress event.
Kill switches
- Either a coordinated earnings re-acceleration or a credit-stress shock would invalidate this base.
Bull case
Probability 20% · fair value 5,560
AI capex sustains a second leg of margin expansion; broad earnings revisions re-accelerate; index makes new highs through Q4.
Drivers
- Q3 earnings revisions inflect positive on broad participation — not just five names.
- Long-end real rates retrace below 2.0% on cooler inflation prints.
- Breadth recovers: % above 200d MA returns above 60%; ad-line slope turns positive.
- Hyperscaler capex translates to a measurable productivity-led margin uplift in non-tech sectors.
Kill switches
- If breadth fails to broaden by mid-summer, the cap-weight rally is hollow and reverts to base.