AI Stress Index Methodology
Last updated – February 2026
What the AI Infrastructure Stress Index measures
The AI Infrastructure Stress Index is a single number between 0 and 100. It answers one question: is AI a bubble, or can the current pace of AI infrastructure spending pay for itself?
Twelve public data signals feed into a weighted composite, updated daily. Weights are derived using the same multi-criteria framework the OECD, UN, and World Bank use for their composite indexes. Higher means more stress. Lower means the buildout looks financially sustainable.
We don't predict crashes or recommend trades. The score tracks how far apart AI capex spending and revenue are, and whether that gap is growing.
The 12 AI bubble signals
Organized into three tiers by information type.
The premium investors demand to hold debt from AI infrastructure companies (CoreWeave, data center operators, GPU lessors) over risk-free Treasuries. Widening spreads mean lenders are pricing in higher default risk. Credit markets have repriced risk 6–18 months ahead of equity markets before every major correction of the last 30 years, which is why this signal carries the most weight. Source: FRED, FINRA TRACE. Updated daily.
TSMC monthly revenue, SIA global chip sales, and SEMI equipment book-to-bill ratios. NVIDIA's revenue today depends on orders placed 6–12 months ago, so the semiconductor supply chain is where demand inflections show up first. When book-to-bill drops below 1.0 or TSMC revenue growth decelerates, trouble is coming. This cycle has called every tech correction in the last 25 years. Updated monthly via SIA, TSMC investor relations, and SEMI.
Put/call ratios, options skew, and implied volatility for AI-exposed stocks (NVDA, SMCI, ARM, AI ETFs). When hedge funds and market makers are hedging or betting against AI, it shows up in options flow before stock prices move. Source: CBOE, OCC. Updated daily.
Real-time spot pricing for GPU compute across AWS, Azure, GCP, Vast.ai, and Lambda Labs. The logic is simple: if AI demand is real, GPU spot prices should be stable or rising. Falling prices mean more capacity has been built than buyers need, a direct GPU oversupply indicator. This is the most direct physical measure of whether infrastructure investment matches actual demand. Updated daily via cloud provider APIs.
How much of their operating cash flow Microsoft, Alphabet, Amazon, and Meta are plowing back into AI infrastructure. When this ratio approaches 100%, they're spending everything they earn. Past 100%, they're borrowing to build. Current hyperscaler capex runs at 45–57% of revenue, which exceeds AT&T's spending at the peak of the telecom bubble. Source: SEC quarterly filings. Updated quarterly.
Not whether NVIDIA is growing, but whether growth is accelerating or slowing. Revenue can still be rising while the rate of growth falls. That deceleration is the signal. Here's the math:
Where is quarterly revenue and is the year-over-year growth rate. When turns negative, growth is decelerating even if revenue is still climbing. Cisco's growth rate decelerated for two quarters before the dot-com crash, while the company was still reporting record revenue. Source: NVIDIA quarterly earnings via SEC EDGAR. Updated quarterly.
Net insider selling (SEC Form 4 filings) across NVIDIA, AMD, Microsoft, Alphabet, Amazon, Meta, Broadcom, and AI-focused post-IPO companies. Corporate insiders know their own demand pipelines. Concentrated insider selling accelerated at Cisco, Lucent, and WorldCom months before the dot-com crash. Form 4 filings are legally required within 2 business days, so the data is close to real-time. Source: SEC EDGAR. Updated daily.
Equinix and Digital Realty Trust stock performance relative to the broader REIT index (VNQ). These are the most direct public equity proxy for data center demand. When they underperform the broader REIT index, equity investors are losing confidence in data center demand growth. We also track occupancy rates and leasing spreads from their quarterly filings. Updated daily for price data, quarterly for fundamentals.
NLP analysis of S&P 500 earnings call transcripts and SEC filings. We track how the tone around AI shifts: from "transformative opportunity" to "measured approach" to "rationalizing spend." That language shift tends to precede guidance cuts by 3–6 months. This is the lowest-weighted signal because sentiment analysis is newer and less battle-tested than the financial signals above. Updated quarterly.
Stock performance of enterprise AI adopters — Snowflake, Salesforce, ServiceNow, and Palantir — relative to the S&P 500 (SPY) over a 90-day rolling window. If the companies that are supposed to be benefiting from AI investments are underperforming the broad market, the ROI thesis underlying hyperscaler spend is failing. This is the demand-side check on the supply-side buildout. Source: Polygon.io. Updated daily.
Vertiv (VRT) and Eaton (ETN) — the picks-and-shovels companies providing power and cooling infrastructure for data centers — relative to the broad industrials sector (XLI) over a 90-day rolling window. These companies reflect physical data center buildout demand 6–12 months ahead of revenue realization. When they underperform industrials, it signals that demand for physical AI infrastructure may be decelerating. Source: Polygon.io. Updated daily.
Nuclear and power companies positioned for AI data center energy demand — Constellation Energy (CEG), Vistra (VST), NRG Energy (NRG) — relative to the broad utilities sector (XLU) over a 90-day rolling window. Power is the binding constraint on data center buildout. Dramatic outperformance vs. utilities indicates the market is pricing in unsustainable AI power demand expectations. This is the only signal measuring physical energy infrastructure demand, completely independent of financial markets or equity sentiment. Source: Polygon.io. Updated daily.
Why these weights
The most common criticism of composite indexes: "Why 15% and not 12%?" Without a framework, that question has no answer.
We score each signal 1–5 on five dimensions, then derive weights proportionally from the totals:
Where is the total score for signal across all five dimensions. The denominator is the sum of all twelve signal scores (237 in our case). This is what the OECD Handbook on Constructing Composite Indicators calls the "Budget Allocation Process." The UN Human Development Index and World Bank Doing Business Index use the same method.
The five dimensions:
- ·Lead time measures how far in advance of a crisis the signal moves. Leading indicators get more weight.
- ·Update frequency. Daily data is worth more to a daily-updating index than quarterly data.
- ·Data reliability is about the source. Audited SEC filings and Federal Reserve data rank higher than web-scraped estimates.
- ·Historical precedent. How well has this type of signal called past bubbles? Track records matter.
- ·Uniqueness asks whether the signal adds information the others don't. Correlated signals shouldn't double-count the same risk.
The resulting range is 6%–11%, compared to a pure equal weight of 8.3% per signal. Credit spreads score highest on every dimension. Enterprise AI sentiment scores lowest because the methodology is newer and partially correlated with other fundamentals.
That convergence toward near-equal weighting is expected. An IMF paper (Brave & Butters, 2022) found that equal-weight financial conditions indexes perform comparably to more complex statistical approaches. The structure gives justified deviation from equal weight without arbitrary extremes.
Weights are reviewed annually. When we have 12+ months of continuous data, we'll publish a PCA validation study comparing statistically-derived weights against these multi-criteria weights.
How the AI stress score is calculated
Each signal is normalized to a 0–100 scale. 0 means no stress. 100 means maximum stress. At launch, normalization uses min-max scaling against theoretical floor and ceiling values derived from historical extremes:
Clamped to [0, 100]. All signals are sign-aligned so that higher always means more stress.
Once we have 12+ months of data, we'll move to percentile ranking against observed history, which is the method SentimenTrader and most professional composite models use. Percentile ranking is more resistant to outliers and self-calibrates as more history accumulates.
The composite score is a weighted average of all twelve normalized signals:
Where is the weight from the multi-criteria framework and is the normalized score. All weights sum to 1.0. Linear aggregation means a low-stress reading on one signal can offset a high-stress reading on another. One signal spiking while everything else is calm matters less than several rising together.
If a signal can't be updated (data source outage, API failure), the most recent valid value is carried forward for up to 30 days. After that, the signal is excluded and remaining weights rescale to sum to 100%. Any exclusion is flagged on the site.
The composite updates daily at market close. Eight signals update daily or better (credit spreads, GPU pricing, data center REITs, insider trading, options sentiment, AI adopter performance, data center infrastructure, AI power demand). One updates monthly (semiconductor supply chain). Three update quarterly (NVIDIA growth, hyperscaler capex, enterprise sentiment). When a quarterly signal updates, say after NVIDIA earnings, the composite may shift more in a single day. That's expected. The site shows the "as of" date for each signal so you can tell which data is fresh and which is carried forward.
Score zones – from Green (no bubble) to Red (bubble likely)
AI spending looks justified by current demand trends. Credit markets are calm, GPU capacity is being absorbed, growth is accelerating.
Early signs of strain. Some signals are elevated, but nothing systemic. Worth watching.
Multiple signals flashing stress. The gap between spending and revenue is widening, credit conditions are tightening, or growth is decelerating. This is where the score sits today.
Broad stress across most signals. This kind of pattern preceded corrections in previous infrastructure buildouts (fiber/telecom in 2000, housing in 2007).
The 25-point zones are chosen for simplicity. They aren't statistically derived. With limited history, there's no empirical basis for optimizing thresholds yet. As data accumulates, zone boundaries may be adjusted, with changes announced in advance.
Theoretical foundations
The index draws on three frameworks from financial economics. Michael Burry's AI prediction draws on similar foundations, though our index tracks the data directly rather than making timing calls.
Minsky's Financial Instability Hypothesis. Long periods of stability encourage risk-taking until the system becomes fragile. Borrowers evolve through three stages: hedge finance (cash flow covers all obligations), speculative finance (can cover interest but must refinance principal), and Ponzi finance (can't cover interest or principal). Our credit spread and capex/cash flow signals are built to catch this transition in AI infrastructure.
Kindleberger's Five Bubble Stages. Displacement (ChatGPT launch), boom (hyperscaler capex ramp), euphoria (AI = 92% of GDP growth), profit-taking/distress, panic. The index targets the transition from stage three to stage four. That's the highest-value moment for anyone watching.
Credit-to-GDP cycle analysis. Fed, IMF, and BIS research all point to the same finding: the rate of change of credit, not its absolute level, predicts financial crises. AI-related debt issuance exceeds $200B in 2025. JPMorgan projects data center paper will reach 7-10% of structured credit issuance by 2026-2027. AI infrastructure accounts for 4% of GDP but drove 92% of GDP growth in H1 2025. The question of AI spending sustainability comes down to whether this credit growth can be serviced by actual revenue.
Data sources
All data comes from public sources. Nothing is proprietary or paywalled at the source level.
- ·Credit spreads: FRED (Federal Reserve Economic Data), FINRA TRACE
- ·GPU spot pricing: AWS, Azure, GCP, Vast.ai, Lambda Labs public APIs
- ·NVIDIA financials: quarterly earnings via SEC EDGAR
- ·Hyperscaler financials: quarterly earnings from Microsoft, Alphabet, Amazon, Meta (SEC EDGAR)
- ·Earnings call transcripts: SEC EDGAR filings
- ·Semiconductor data: SIA (Semiconductor Industry Association), TSMC investor relations, SEMI
- ·Data center REITs: market data for EQIX, DLR, VNQ; quarterly SEC filings
- ·Insider trading: SEC Form 4 filings via EDGAR
- ·Options data: CBOE, OCC (Options Clearing Corporation)
- ·AI adopter performance: market data for SNOW, CRM, NOW, PLTR, SPY via Polygon.io
- ·Data center infrastructure: market data for VRT, ETN, XLI via Polygon.io
- ·AI power demand: market data for CEG, VST, NRG, XLU via Polygon.io
What this doesn't measure
The AI Infrastructure Stress Index is focused on one thing: the financial sustainability of AI infrastructure spending. That narrow focus is deliberate. It means the index does not cover:
- ·Whether AI technology is valuable (it is)
- ·Individual stock prices or short-term market moves
- ·Geopolitical risk, regulation, or policy changes
- ·Spending by governments or defense contractors
- ·The pace of AI research breakthroughs
A high score doesn't mean AI is failing. It means the money being spent on AI infrastructure may not generate enough return to justify itself.
Limitations
Some signals have decades of history (credit spreads, semiconductor data). Others have 1–3 years (GPU spot pricing, AI-specific credit). Normalization and weight calibration will get better as history accumulates.
Three of twelve signals update quarterly. Between updates, those signals carry forward stale values, which means the composite can underreact to fast-moving conditions in those dimensions.
The multi-criteria framework is more structured than pure expert judgment, but the criteria scores still involve judgment. We tested this: perturbing weights by ±3 percentage points across 10,000 simulations produces deviations of less than ±2.5 points on the composite. The score is not fragile.
In a real downturn, signals tend to move together. The individual signal breakdown, available to Pro subscribers, helps isolate which risk dimensions are driving the composite.
And one more thing: the score measures current stress, not timing. The 2008 housing market was unsustainable for years before the crash. A high score means stress is elevated. It doesn't tell you when.
Changelog
Launch with 9 active signals across three tiers.
Expanded to 12 signals. Added AI Adopter Relative Performance (8%), Data Center Infrastructure Performance (9%), and AI Power Demand (8%). All weights rebalanced: Credit & Financial Risk (27%), Fundamental & Operational Stress (25%), Sentiment & Behavioral (48%).
The data updates daily. The methodology stays transparent.