Historical Market Conditions: 1929, Dot-Com, and Today
Selected historical-peak conditions compared with dated recent observations.
A descriptive comparison of market conditions, with separate definitions for different eras and explicit limits on comparability.
Version 1.0-Redacted · Data cutoff: October 25, 2026. Observation dates vary by measure.
Abstract
This study compares market conditions surrounding the 1929 and dot-com equity-market peaks with the latest observations available by October 25, 2026. It examines five broad themes: enthusiasm for transformative technology, valuations dependent on exceptional growth, investor borrowing, changes in policy and corporate borrowing rates, and speculative participation. Quantitative measures are placed within their available historical distributions using endpoint-normalized percentiles and scores from 1 to 10, without excluding crash periods. Separate reference distributions and era-specific proxies are used where definitions or coverage differ.
How to read the comparison
Purpose and selection. This is a retrospective comparison of two selected historical episodes with recent conditions. It is not a representative sample of all crashes, a controlled test of crash causes, or a forecasting model. Measures and era-specific technology groups were selected during the investigation rather than specified in advance; their historical resemblance should therefore be treated as exploratory.
Three classifications. Primary identifies seven retained measures with elevated readings in both selected historical episodes, subject to their stated definitions and sensitivities. It does not mean that all seven are independent, causal or validated predictors. Other provides additional historical context where elevation, coverage or comparability is less consistent. Conditions to watch contains modern monitoring measures and observations without an established shared historical match. These are descriptive classifications, not confidence grades.1
Percentiles, scores and evidence strength
Each value is ranked within its specified reference history. Ties receive their average rank. The endpoint-normalized percentile is 100 × (rank − minimum rank) / (maximum rank − minimum rank); the score is 1 + 0.09 × percentile. Thus the lowest observed value scores 1 and the highest scores 10. This rank transformation describes historical standing; it does not measure the size of an economic effect or the probability of a crash.
The same score can have different evidential strength. For example, a maximum among 20 quarterly BDC flow observations has much less historical coverage than a high rank among 1,749 monthly Indicator A02 observations. Overlapping windows and persistence also mean the observations are not independent samples. Where definitions differ, separate reference distributions describe each series relative to its own history; equal percentiles do not establish equal absolute leverage or equal risk.
All eligible observations in each defined reference panel are used without excluding crash periods, subject to the documented data-quality exclusions. Full-history ranks can include observations after the historical event, and revised data may differ from contemporary releases. They describe the historical record available for this study, not a signal reconstructed solely from information investors possessed at the time.
Colors. Latest cells are pale red at or above the 90th percentile, pale orange from the 80th to below the 90th, and pale green below the 80th. Green means a lower historical rank, not a safe investment or an absence of risk. Supplementary cells retain blue without percentile-based grading. Missing or unassigned measurements are not zero.
Timing and cross-era comparability
“Latest” means the most recent observation used in the saved source snapshot available by October 25, 2026; it does not mean every value was measured on that date. Current observations range from completed 2025 annual data and early-2026 fund flows to October 23, 2026 market prices. The reference notes identify each period and sample.
The historical columns also combine different measurement dates: many monthly measures use August 1929 and February 2000; index measures use August 30, 1929 and March 24, 2000 for the selected Dow and Nasdaq-100 comparisons; corporate funding uses 1999 Q4. The Nasdaq-100 comparison follows its own late-March peak, rather than the Nasdaq Composite’s earlier peak. Annual 1929 investment and GDP denominators include post-peak months and are historical context, not a clean pre-crash snapshot. These differences prevent reading an entire column as one synchronized set of observations.
Five broad historical conditions
These themes organize the comparison; assigning a measure to a theme does not establish a shared crash condition. Corporate internal funding is related funding-dependence context, not a measure of margin borrowing. Realized volatility is related price behavior, not direct evidence of speculative participation.
- Optimism about transformative technology
- (Primary) Indicator A01
- (Other) Indicator B01
- Prices dependent on exceptional future growth
- (Primary) Indicator A02, Indicator A03, Indicator A04, Indicator A05
- (Other) Indicator B02
- Investor leverage and funding dependence
- (Primary) Indicator A06, Indicator A07
- (Other) Indicator B03, Indicator B04, Indicator B05
- (Watch) Indicator C01, Indicator C02, Indicator C03
- Interest rates and financing terms
- (Other) Indicator B06, Indicator B07
- (Watch) Indicator C04, Indicator C05
- Speculative participation and demand for new securities
- (Other) Indicator B08, Indicator B09
- (Watch) Indicator C06
Primary historical-condition indicators1
| Indicator | 1929 | Dot-com | Latest |
|---|---|---|---|
| Indicator A012 | +27.65 pp | +59.87 pp | +47.32 pp |
| - Percentile / Score | 99.1% / 9.92 | 99.7% / 9.98 | 97.7% / 9.79 |
| Indicator A023 | 31.48× | 42.19× | 40.58× |
| - Percentile / Score | 93.8% / 9.44 | 99.4% / 9.94 | 98.9% / 9.90 |
| Indicator A034 | +0.47 pp | +1.28 pp | -0.82 pp |
| - Percentile / Score | 96.1% / 9.65 | 99.3% / 9.93 | 83.2% / 8.49 |
| Indicator A045 | +59.23% | +133.00% | +15.38% |
| — Percentile / Score | 98.9% / 9.90 | 100.0% / 10.00 | 44.8% / 5.03 |
| Indicator A056 | +26.31% | +65.97% | +5.98% |
| — Percentile / Score | 98.8% / 9.89 | 100.0% / 10.00 | 38.7% / 4.48 |
| Indicator A067 | +56.05% | +74.46% | +31.39% |
| - Percentile / Score | 87.9% / 8.91 | 99.7% / 9.97 | 82.6% / 8.43 |
| Indicator A078 | +66.49% | +81.98% | +50.00% |
| - Percentile / Score | 98.7% / 9.89 | 99.7% / 9.97 | 95.0% / 9.55 |
Other historical condition indicators
| Indicator | 1929 | Dot-com | Latest |
|---|---|---|---|
| Indicator B019 | 11.06% | 14.17% | 14.15% |
| — Percentile / Score | 34.4% / 4.09 | 94.8% / 9.53 | 93.8% / 9.44 |
| Indicator B0210 | ≈124.4% | 163.8% | 287.5% |
| — Percentile / Score | Unassigned | 72.9% / 7.56 | 100.0% / 10.00 |
| Indicator B0311 | +7.54% | +2.77% | +4.55% |
| - Percentile / Score | 99.3% / 9.94 | 73.6% / 7.62 | 99.7% / 9.97 |
| Indicator B0412 | $153.5B | $564.0B | $1,480.1B |
| - Percentile / Score | 99.6% / 9.96 | 50.7% / 5.56 | 99.7% / 9.97 |
| Indicator B0513 | — | 134.49% | 92.87% |
| — Percentile / Score | Not available | 97.0% / 9.73 | 15.5% / 2.39 |
| Indicator B0614 | +0.74 pp | +0.99 pp | -0.52 pp |
| — Percentile / Score | 86.4% / 8.78 | 81.0% / 8.29 | 33.8% / 4.04 |
| Indicator B0715 | +0.43 pp | +0.90 pp | +0.64 pp |
| — Percentile / Score | 74.7% / 7.73 | 87.4% / 8.87 | 81.7% / 8.35 |
| Indicator B0816 | +991.7% | +144.3% | +1,400.4% |
| — Percentile / Score | 94.8% / 9.54 | 84.1% / 8.57 | 99.2% / 9.93 |
| Indicator B0917 | 23.19% | 45.64% | 18.45% |
| — Percentile / Score | 88.4% / 8.95 | 94.2% / 9.48 | 51.9% / 5.67 |
Conditions to watch
Modern-only measures are ranked within their own available histories; unavailable crash-era values remain blank. These are descriptive monitoring measures, not established shared crash conditions.
| Indicator | 1929 | Dot-com | Latest |
|---|---|---|---|
| Indicator C0118 | — | — | 2.52× |
| — Percentile / Score | Not available | Not available | 90.6% / 9.15 |
| Indicator C0219 | — | — | 8.20× |
| — Percentile / Score | Not available | Not available | 98.1% / 9.83 |
| Indicator C0320 | — | — | 2.73× |
| — Percentile / Score | Not available | Not available | 93.4% / 9.41 |
| Indicator C0421 | — | — | 0.00% |
| — Percentile / Score | Not available | Not available | 48.3% / 5.35 |
| Indicator C0522 | — | — | 5.88% |
| — Percentile / Score | Not available | Not available | 78.3% / 8.05 |
| Indicator C0623 | +38.9% | +43.6% | +4.2% |
| — Percentile / Score | 73.6% / 7.62 | 90.2% / 9.12 | 41.6% / 4.74 |
Supplementary indicators and context
This Version 1.0 retains eight supplementary entries across two categories: AI financing and earnings quality risks, and institutional leverage and funding dependence risk. Validated corporate funding and modern leverage/dealer measures now appear above, with their historical ranks and limitations in references.
No supplementary composite or predictive weight is assigned. Dates, definitions, coverage and the remaining validation requirements appear in the numbered references and linked evidence.
AI financing and earnings quality risks
| Supplementary indicator24 | Latest available, October 25, 2026 |
|---|---|
Indicator S01VulnerabilityDefinition and limitsDisclosed customer investments, loans and financing support; separately identify related revenue and actual cash receipts. Express supported demand as a share of revenue only where traceable. A supplier or investor may depend on the same customer funding cycle. Trace transaction overlap before measuring exposure; a financing relationship alone does not show improper accounting. | Selected financing link, not the size of circular revenue. Industry-wide supported-demand share unquantified. Source / evidence |
Indicator S02VulnerabilityDefinition and limitsOperating cash flow versus earnings; receivables and contract assets versus revenue; days sales outstanding; contribution from customer prepayments. Use trailing-four-quarter and year-over-year comparisons. Cash collections lagging reported earnings, or cash flow depending heavily on new advances, may expose funding needs. Growth and payment timing can also explain the difference. | Cash-flow contribution is not a finding of improper revenue recognition. Sector OCF/earnings panel not assembled. Source / evidence |
Indicator S03VulnerabilityDefinition and limitsCash capex / operating cash flow, cash deficit after capex, and funding sources; leases reconciled separately. Compare like periods. Spending exceeding internally generated cash creates a financing requirement; it does not itself prove distress. | Different periods and firms; these are examples, not an AI-sector ratio. Source / evidence |
Indicator S04VulnerabilityDefinition and limitsUnavoidable payments due within 12/24 months versus unrestricted cash and available committed facilities; distinguish lease liabilities, guarantees and purchase commitments. Large near-term obligations or concentrated guarantees can amplify a revenue or funding shortfall. Do not add overlapping commitment totals. | Different exposures: do not sum. NVIDIA guarantees activate in phases, first expected FY2029, and are not current losses or all immediately payable. Source / evidence |
Indicator S05VulnerabilityDefinition and limitsChanges in server useful lives, depreciation, capitalized costs, revenue timing, impairment assumptions and GAAP/non-GAAP reconciliation; quantify disclosed earnings effects. Assumptions may change reported earnings or obscure comparability. Adjust only for documented effects; accounting differences are not evidence of misconduct. | Disclosed accounting policy only. No improper estimate, recent extension, sector earnings effect or quantified haircut established. Source / evidence |
Indicator S06VulnerabilityDefinition and limitsCustomer concentration, cancellations, backlog conversion, data-center utilization, compute pricing and margins; distinguish contracted backlog from recognized revenue. Unused capacity, cancellations or dependence on a small customer set can expose an investment/funding mismatch. | Company-specific concentration; utilization, cancellations and sector concentration remain unquantified. Source / evidence |
Indicator S07VulnerabilityDefinition and limitsDebt maturities within 12/24 months; cash and committed liquidity; interest coverage; floating-rate exposure; refinancing spreads. Insufficient cash or earnings to cover interest and maturities can create refinancing stress. | Selected balance-sheet context only. Availability is conditional; no complete 12/24-month obligations-to-liquidity or sector coverage ratio calculated. Source / evidence |
Institutional leverage and funding dependence risk
| Supplementary indicator25 | Latest available, October 25, 2026 |
|---|---|
| Indicator S0825Supplementary context · separately scored components | PIK and valuation results are chart estimates. Nonaccrual history and valuation opacity remain unscored. No combined S08 score is assigned.25 Analysis, reference periods, sources and limits |
How this context is used
- Distinguish company disclosures, dealer-survey assessments and aggregate funding ratios; preserve their dates and coverage.
- Retain contrary evidence and identify missing measurements explicitly.
- Keep overlapping exposures separate from independent evidence; do not add related amounts or count related entries as separate confirmations.
- Accounting policies and financing relationships alone do not establish misconduct or improper reporting.
- Treat the observations as dated descriptive context, without assigning a supplementary composite score or a trading signal.
Remaining comparison limits
Interpretation
Where the resemblance is strongest.
Where the comparison differs.
What remains unresolved.
Conclusion.
Sources
Primary sources include Shiller valuation data, Federal Reserve policy rates, Moody’s Baa yields via FRED, Federal Reserve financial accounts and dealer surveys, OFR / SEC Form PF statistics, BEA national accounts, FINRA margin statistics, historical NBER series, and company filings. Individual references identify the applicable source and observation period.
The supporting studies provide calculations, source reconciliation and sensitivity analysis. Some retain earlier exploratory methods or classifications; the interpretation and classifications in this Version 1.0 take precedence. Data remain those of the saved study snapshot available by October 25, 2026; this version does not substitute newly downloaded values or claim a new independent data audit.
References and definitions
Classification and selection limits
Indicator A01
Indicator A02
Indicator A03
Indicator A04
Indicator A05
Indicator A06
Indicator A07
Indicator B01
Indicator B02
Indicator B03
Indicator B04
Indicator B05
Indicator B06
Indicator B07
Indicator B08
Indicator B09
Indicator C01
Indicator C02
Indicator C03
Indicator C04
Indicator C05
Indicator C06
Supplementary indicators S01–S07
Indicator S08
Shared index definitions and dates
Source amounts and comparability