The everything bubble

Is it a bubble if every major asset class is overvalued at the same time — or is that just what a higher price level looks like in a larger monetary base? The question is sharper than it sounds, because the answer changes what you do with the next ten years of savings. The phrase “Everything Bubble” gets thrown around loosely, but it has a precise meaning. It refers to the fifteen-year span between the 2008 financial crisis and the 2022 inflation shock, during which the world's major central banks — led by the Federal Reserve — expanded their balance sheets by an order of magnitude and held real interest rates near or below zero. The Fed alone went from $900 billion in assets to nearly $9 trillion. In that window, every major asset class — US equities, Treasuries, corporate bonds, residential housing, commercial real estate, gold, fine art, vintage wine, collectible cars, and a new asset class called crypto — rallied together. Not because they each had good fundamentals. Because they were all responding to the same input: an unprecedented expansion of monetary base, looking for somewhere to land.

This is precisely the outcome that classical portfolio theory said could not happen for long. The intellectual scaffolding of every retirement account in America — Markowitz mean-variance optimization, the Capital Asset Pricing Model, the textbook 60/40 portfolio — rests on the assumption that different asset classes have different risk drivers and therefore move out of phase. From roughly 1990 to 2007, that assumption held up beautifully. US stocks and US Treasuries carried a mildly negative correlation, around −0.3. When growth fears hit equities, the Fed cut rates and bonds rallied. When the economy boomed and bonds sold off, equities did well. Diversification through asset classes was the closest thing finance had to a free lunch, and the 60/40 portfolio earned roughly nine percent a year with smoother returns than either leg alone.

Quantitative easing broke that machinery, and it did so by the most elementary mechanism imaginable: when one buyer is large enough to bid for everything, everything starts to move together. The Fed bought Treasuries directly, removing them from the market and forcing yields lower. The cash it credited to primary dealers' reserve accounts did not stay parked; it bid for mortgage-backed securities, then corporate bonds, then equities, then anything with a yield. Lower discount rates lifted every multiple in every market, because every multiple is a present-value calculation with a discount rate in the denominator. Real estate, growth stocks, venture capital, art, even speculative crypto — all of them benefitted from the same monetary fuel. Diversification by asset class became, structurally, a single bet on the persistence of cheap money.

The consequence is visible in the correlation data. The stock-bond correlation, that linchpin of the 60/40, flipped from approximately −0.3 in the pre-2008 era to roughly +0.5 across the QE years. The diversification benefit shrank to nearly nothing — both legs of the portfolio were responding to the same liquidity factor. When M2 expanded, both rose. When M2 contracted, both fell. The illusion held only as long as M2 went in one direction.

2022 was the year the illusion broke. Faced with the first sustained inflation in forty years, the Fed lifted the federal funds rate by 425 basis points in nine months — the fastest tightening cycle since Paul Volcker — and began draining its balance sheet for the first time in modern history. The S&P 500 fell approximately 19%. The Bloomberg US Aggregate bond index fell approximately 13%. A standard 60/40 portfolio lost roughly 17% in real terms. According to the standard historical databases, that was the worst calendar year for a 60/40 portfolio in over a century. The mechanism that was supposed to hedge — bonds rallying when stocks sold off — did not just fail; it inverted, because both legs had been inflated by the same factor and were being deflated by the same factor in reverse. The diversification was not gone in 2022. It had been gone for thirteen years. 2022 was simply the year the market reminded everyone of that fact.

Look at where the major valuation metrics sit today. The Shiller CAPE ratio — Robert Shiller's cyclically adjusted price-to-earnings measure, the longest valuation series available — stands at roughly 36, a level matched only in 1929 and 2000. The Buffett Indicator, total US stock-market capitalization divided by GDP, has crossed 200% — the highest reading in recorded history. US housing now consumes roughly 42% of median disposable income, against a long-run norm closer to 26%, making it the least affordable in modern American history by some measures. Commercial real estate cap rates compressed from a historical 8% to about 5% during the QE era, embedding leverage everywhere a building has to be refinanced. None of these levels guarantees an imminent crash. Every one of them guarantees that forward expected returns from these prices are structurally lower than the trailing fifteen years implied.

There are five scenarios in which the Everything Bubble materially deflates, and you should understand all of them rather than picking your favorite. The first is persistent inflation, in which the Fed is forced to keep real rates elevated for years, multiples compress 30-50%, and long-duration assets — growth stocks, 30-year Treasuries, prime real estate — get repriced for the new discount-rate regime. The second is recession, in which earnings fall sharply but inflation has cooled enough that the Fed can ease aggressively; this is the “Fed put” scenario, and it is the one most investors are quietly betting on. The third is a geopolitical shock — Taiwan, the Middle East, a sudden capital-flight event from a major emerging market — that produces a brief dollar spike followed by a structural dollar weakening. The fourth is demographic exhaustion, in which boomers liquidate retirement accounts into a thinner millennial buyer base and produce a long, grinding real-terms deflation in financial assets while nominal prices appear stable. The fifth is the deepest and least discussed: loss of dollar reserve status, in which BRICS-plus settlement systems mature, the dollar's share of global reserves drops below 50%, and the “exorbitant privilege” that has subsidized US asset prices for fifty years reverses.

The portfolio implication is harder to ignore than the diagnosis. The 60/40 is not the answer to a market in which stocks and bonds are co-driven by liquidity, because there is no diversification inside the two-asset universe when both assets share a factor. The historical pattern across every previous late-stage debt cycle is consistent: hard assets — gold, productive real estate, energy, broad commodities — hold or gain real value while paper claims debase. Shorter duration matters more than longer duration when long bonds are no longer a hedge. And cash, dismissed for fifteen years as “trash,” is again paying real after-tax yields for the first time since 2007. None of this means abandoning equities — companies with genuine pricing power and low debt outperform across every regime — but it does mean that the post-2008 playbook is over. The next fifteen years will not look like the last fifteen, and the portfolios that simply mirror what worked in the QE era will pay the bill for that mismatch.