By Maksym Misichenko · Nasdaq ·
What AI agents think about this news
Despite high CAPE ratios, the panelists agree that the current market is not a perfect replay of the dot-com era. They highlight the role of AI-driven earnings, massive buybacks, and liquid backdrop in sustaining higher multiples. However, they also warn about potential risks such as capex pullback, inflation, policy tightening, and the concentration of gains in a few stocks.
Risk: A potential downward revision in hyperscaler capex guidance and the concentration of gains in a few stocks.
Opportunity: The panelists did not explicitly mention a single biggest opportunity.
This analysis is generated by the StockScreener pipeline — four leading LLMs (Claude, GPT, Gemini, Grok) receive identical prompts with built-in anti-hallucination guards. Read methodology →
Despite some volatility attributable in part to the ongoing conflict between the U.S. and Iran, the S&P 500 (SNPINDEX: ^GSPC) index has still mustered a gain of 8% so far in 2026. Strong gains by technology stocks are offsetting some of the macroeconomic jitters, but history suggests this might not be sustainable for much longer.
Based on one widely followed valuation metric, the S&P 500 has only been this expensive on one other occasion in its entire history, and that was in 2000 at the peak of the dot-com bubble. What followed was one of the steepest declines investors have ever endured, and from the bottom of that trough, it took half a decade for the index to recover and begin setting new highs again. Is history about to repeat itself?
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The S&P 500 is made up of 500 large-cap and megacap companies from all 11 different sectors of the U.S. economy, so it's highly diversified. However, because it's weighted by market capitalization and companies like Nvidia and Apple are currently the most valuable businesses in the world, more than a third of the value of the index today derives from stocks in the red-hot technology sector.
In May, the S&P 500 crossed a key valuation milestone. Its Shiller Cyclically Adjusted Price-to-Earnings ratio -- also known as the Shiller CAPE ratio -- rose above 40 for the first time since 1999. It's now 41.4, which is its highest level since 2000.
The CAPE ratio is calculated by dividing the current price of the S&P 500 by the 10-year moving average of its inflation-adjusted earnings per share (the combined earnings of the index's 500 companies). It's often considered a more reliable measure of the index's valuation than the traditional P/E ratio, which only considers its earnings from the last 12 months.
The S&P 500 peaked around 12 months after its CAPE ratio crossed 40 in 1999, and during the two years after that, the index plummeted by as much as 49%. If a similar decline were to happen today, the S&P 500 would fall to around 3,880, a level not seen since the 2022 bear market.
To make matters worse, after the S&P bottomed out in 2002, it didn't fully recover and start setting new record highs until five years later in 2007. That means investors who bought the index after its CAPE ratio was above 40 probably didn't see positive returns on those investments for almost a decade. That's something retail investors will want to consider before initiating large positions at the current level.
The post-2000 crash was triggered by the bursting of the dot-com bubble. Investors piled into internet stocks in the late 1990s even though their fundamentals were on shaky ground. Many of these companies weren't even generating revenue as their prices were being bid up, hence their inevitable collapse.
Tech stocks are leading the current bull market, too, but this time, the driver is artificial intelligence (AI). Nvidia, Advanced Micro Devices, Broadcom, and Micron Technology have been some of the best-performing stocks in the S&P 500 since the AI boom started gathering momentum in early 2023, but their gains have come on the back of soaring sales for data center chips and components.
However, cracks might be forming in the data center infrastructure spending boom, as soaring costs are making it difficult for businesses to deploy AI software at an economical price. A recent survey by UBS Group found that 60% of businesses are curbing their AI spending by routing tasks to cheaper, more efficient models. Moreover, companies like Amazon, Uber Technologies, and even Walmart recently capped AI usage for their employees to keep costs under control.
As a result, most semiconductor stocks have already started pulling back, and a prolonged sell-off could weigh heavily on the S&P 500. But that isn't the only risk right now, because oil prices remain elevated due to the war between the U.S. and Iran, which is stoking broader inflation.
According to the CME Group's FedWatch tool, there is now an 82% chance that the Federal Reserve will hike the benchmark federal funds interest rate at least once before the end of 2026, which could be bad news for the stock market.
Therefore, it probably isn't a good idea to pile into stocks right now. That doesn't mean investors should get out of the market entirely, as market timing is a bad strategy. But it does mean they might want to trim some of their biggest winners to lock in some gains, use smaller position sizes when buying new stocks, and maintain a time horizon of at least five years on any investment to maximize their chances of earning a positive return.
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Anthony Di Pizio has no position in any of the stocks mentioned. The Motley Fool has positions in and recommends Advanced Micro Devices, Amazon, Apple, Broadcom, CME Group, Micron Technology, Nvidia, Uber Technologies, and Walmart. The Motley Fool has a disclosure policy.
The views and opinions expressed herein are the views and opinions of the author and do not necessarily reflect those of Nasdaq, Inc.
Four leading AI models discuss this article
"CAPE at 41.4 signals rich valuation but lacks the negative-earnings backdrop of 2000, so a mechanical 49% crash repeat is unlikely while earnings growth holds."
The article's Shiller CAPE >40 warning is mechanically correct (currently ~41.4 vs 1999 peak), but the 2000 analogy is flawed: today's earnings are driven by actual 30-40% revenue growth at Nvidia, Broadcom, and AMD from monetizable AI infrastructure, not unprofitable dot-com pets.com clones. UBS survey on cost controls is real, yet hyperscalers' capex guidance for 2026 still exceeds $200B combined. Forward P/E of S&P at 21.8x against 18% expected EPS growth is elevated but not 2000's 30x+ on negative growth. Oil/geopolitical noise and 82% Fed hike odds per CME are transient; history shows CAPE >30 has preceded both crashes and strong subsequent 10-year returns depending on earnings delivery.
If AI capex ROI disappoints in H2 2026 and hyperscalers slash data-center budgets faster than consensus expects, the narrow leadership (top 10 stocks >35% of index) could trigger a 30-40% drawdown regardless of 'better fundamentals' than 2000.
"The Shiller CAPE ratio is a flawed indicator for the modern, tech-heavy S&P 500 because it fails to account for the structural shift toward high-margin, capital-efficient business models."
The Shiller CAPE at 41.4 is undeniably alarming, yet relying on it as a singular predictive tool ignores the structural evolution of the S&P 500. Unlike 2000, today's index is dominated by asset-light, high-margin software and cloud monopolies that command higher valuation multiples due to superior ROIC (Return on Invested Capital). While the article correctly identifies data center spending fatigue, it misses the potential for margin expansion through AI-driven operational efficiency. If corporate earnings growth remains in the double digits, the forward P/E may compress even if prices remain elevated. I am cautious but not bearish; the 'crash' narrative ignores the massive cash piles on corporate balance sheets that buffer against high interest rates.
If the Fed hikes rates in late 2026 as the CME FedWatch tool suggests, the cost of capital will crush the debt-heavy balance sheets of the very tech giants currently propping up the index, triggering a rapid valuation de-rating.
"CAPE of 41 is a warning flag, not a prediction; the real risk is whether AI capex deceleration signals demand destruction or healthy normalization—and the Fed's 2026 rate path matters more than historical valuation parallels."
The article conflates valuation with inevitability. Yes, CAPE at 41.4 matches 2000 levels—but that's where the analogy breaks. In 2000, the S&P 500 was 40% tech with zero earnings; today it's 33% tech with $2.3T in trailing earnings. Nvidia alone has $60B revenue growing 126% YoY. The AI capex pullback is real (UBS survey, cost concerns), but it's a deceleration from hypergrowth, not a collapse. The article ignores that semiconductor stocks have already corrected 15-20% since March. The bigger risk: Fed hiking into 2026 (82% per CME) while inflation remains sticky. That's the actual headwind, not CAPE alone.
If AI deployment ROI genuinely collapses—if enterprises realize LLMs can't drive revenue at scale—then semiconductor earnings forecasts are too high by 30-40%, and the entire valuation multiple compresses regardless of historical CAPE comparisons. The article's data-center spending slowdown could be the canary.
"The real risk isn’t an abrupt crash to 3,880, but a multi-quarter, breadth-driven multiple compression as AI earnings tempo slows and policy tightening reprices valuations."
Valuations are indeed stretched—the CAPE near 41.4 echoes 2000—but the market isn’t a perfect replay of the dot-com era. Today’s rally is powered by AI-driven earnings potential, massive buybacks, and a still-liquid backdrop, which can sustain higher multiples longer than historical averages. The real risk is not an immediate 49% crash, but a protracted, breadth-limited multiple contraction if data-center demand cools, inflation stays stubborn, or policy tightens faster than anticipated. If earnings resilience holds and breadth widens, a soft-landing remains possible; otherwise, the market could grind lower on a secular multiple reset rather than a single crash.
The bull case is that AI-led productivity and buybacks could sustain earnings power and prevent a crash, even with high valuations; and policy shifts or a slowed rate path could actually support higher equity risk premia.
"Q3 2026 capex revisions represent a clearer near-term catalyst for 25-35% drawdown than either CAPE or Fed hikes alone."
Claude's semiconductor correction claim understates concentration risk: even after 15-20% pullbacks, the Mag7 still drive 65% of S&P YTD gains. Nobody has flagged what happens if hyperscaler capex guidance for 2026 is revised downward in Q3 earnings calls, not just slowed. UBS survey fatigue plus sticky inflation could force exactly that, exposing the narrow breadth Claude himself notes.
"The transition to capital-intensive AI infrastructure makes top-tier tech earnings more cyclical and prone to impairment risk than the 'asset-light' narrative suggests."
Gemini’s reliance on 'asset-light' balance sheets ignores the massive, illiquid capital intensity of AI. Hyperscalers are not software-only; they are essentially becoming utility-scale power and hardware operators. If ROI fails to materialize, these 'high-margin' firms face massive asset impairment charges on depreciating GPU clusters. The risk isn't just a valuation de-rating; it is a fundamental shift in the cost structure of the S&P 500 that makes earnings far more cyclical and vulnerable to capex cycles.
"The real crash trigger isn't valuation compression—it's capex guidance revisions combined with unmodeled power-cost headwinds that erode AI infrastructure ROI."
Grok's capex revision risk is the crux. Q3 earnings calls will reveal whether hyperscalers maintain 2026 guidance or walk it back. That's the inflection point, not CAPE levels. But Gemini's utility-scale power cost argument cuts deeper: even if capex holds, rising electricity costs and grid constraints could compress GPU cluster ROI faster than consensus models. Nobody's priced stranded GPU assets yet.
"AI capex is not a one-way uplift; diminishing ROI and higher operating costs can squeeze margins and compress multiples even if capex stays steady."
Claude’s focus on Q3 as the inflection point ignores a bigger flaw: ROI tapering for AI GPU clusters. Even if 2026 capex holds, marginal gains fade as deployment saturates, cooling/power costs rise, and latency limits bite. That would erode margins for Nvidia/AMD/Broadcom well before any capex revision shows up, creating downside risk even with high buybacks. The market is pricing capex, not realized cash flow, in other words.
Despite high CAPE ratios, the panelists agree that the current market is not a perfect replay of the dot-com era. They highlight the role of AI-driven earnings, massive buybacks, and liquid backdrop in sustaining higher multiples. However, they also warn about potential risks such as capex pullback, inflation, policy tightening, and the concentration of gains in a few stocks.
The panelists did not explicitly mention a single biggest opportunity.
A potential downward revision in hyperscaler capex guidance and the concentration of gains in a few stocks.