By Greg Ip

To veterans of financial bubbles, there is plenty familiar about the present. Stock valuations are their richest since the dot-com bubble in 2000. Home prices are back to their pre-financial crisis peak. Risky companies can borrow at the lowest rates on record. Individual investors are pouring money into green energy and cryptocurrency.

This boom has some legitimate explanations, from the advances in digital commerce to fiscally greased growth that will likely be the strongest since 1983.

But there is one driver above all: the Federal Reserve. Easy monetary policy has regularly fueled financial booms, and it is exceptionally easy now. The Fed has kept interest rates near zero for the past year and signaled rates won't change for at least two more years. It is buying hundreds of billions of dollars of bonds. As a result, the 10-year Treasury bond yield is well below inflation -- that is, real yields are deeply negative -- for only the second time in 40 years.

There are good reasons why rates are so low. The Fed acted in response to a pandemic that at its most intense threatened even more damage than the 2007-09 financial crisis. Yet in great part thanks to the Fed and Congress, which has passed some $5 trillion in fiscal stimulus, this recovery looks much healthier than the last. That could undermine the reasons for such low rates, threatening the underpinnings of market valuations.

"Equity markets at a minimum are priced to perfection on the assumption rates will be low for a long time," said Harvard University economist Jeremy Stein, who served as a Fed governor alongside now-chairman Jerome Powell. "And certainly you get the sense the Fed is trying really hard to say, 'Everything is fine, we're in no rush to raise rates.' But while I don't think we're headed for sustained high inflation it's completely possible we'll have several quarters of hot readings on inflation."

Since stocks' valuations are only justified if interest rates stay extremely low, how do they reprice if the Fed has to tighten monetary policy to combat inflation and bond yields rise one to 1.5 percentage points, he asked. "You could get a serious correction in asset prices."

'A bit frothy'

The Fed has been here before. In the late 1990s its willingness to cut rates in response to the Asian financial crisis and the near collapse of the hedge fund Long-Term Capital Management was seen by some as an implicit market backstop, inflating the ensuing dot-com bubble. Its low-rate policy in the wake of that collapsed bubble was then blamed for driving up housing prices. Both times Fed officials defended their policy, arguing that to raise rates (or not cut them) simply to prevent bubbles would compromise their main goals of low unemployment and inflation, and do more harm than letting the bubble deflate on its own.

As for this year, in a report this week the central bank warned asset "valuations are generally high" and "vulnerable to significant declines should investor risk appetite fall, progress on containing the virus disappoint, or the recovery stall." On April 28 Mr. Powell acknowledged markets look "a bit frothy" and the Fed might be one of the reasons: "I won't say it has nothing to do with monetary policy, but it has a tremendous amount to do with vaccination and reopening of the economy." But he gave no hint the Fed was about to dial back its stimulus: "The economy is a long way from our goals." A Labor Department report Friday showing that far fewer jobs were created in April than Wall Street expected underlined that.

The Fed's choices are heavily influenced by the financial crisis. While the Fed cut rates to near zero and bought bonds then as well, it was battling powerful headwinds as households, banks, and governments sought to pay down debts. That held back spending and pushed inflation below the Fed's 2% target. Deeper-seated forces such as aging populations also held down growth and interest rates, a combination some dubbed "secular stagnation."

The pandemic shutdown a year ago triggered a hit to economic output that was initially worse than the financial crisis. But after two months, economic activity began to recover as restrictions eased and businesses adapted to social distancing. The Fed initiated new lending programs and Congress passed the $2.2 trillion Cares Act. Vaccines arrived sooner than expected. The U.S. economy is likely to hit its pre-pandemic size in the current quarter, two years faster than after the financial crisis.

And yet even as the outlook has improved, the fiscal and monetary taps remain wide open. Democrats first proposed an additional $3 trillion in stimulus last May when output was expected to fall 6% last year. It actually fell less than half that, but Democrats, after winning both the White House and Congress, pressed ahead with the same size stimulus.

The Fed began buying bonds in March, 2020 to counter chaotic conditions in markets. In late summer, with markets functioning normally, it extended the program while tilting the rationale toward keeping bond yields low.

At the same time it unveiled a new framework: After years of inflation running below 2%, it would aim to push inflation not just back to 2% but higher, so that over time average and expected inflation would both stabilize at 2%. To that end, it promised not to raise rates until full employment had been restored and inflation was 2% and headed higher. Officials predicted that would not happen before 2024 and have since stuck to that guidance despite a significantly improving outlook.

Running of the bulls

This injection of unprecedented monetary and fiscal stimulus into an economy already rebounding thanks to vaccinations is why Wall Street strategists are their most bullish on stocks since before the last financial crisis, according to a survey by Bank of America Corp. While profit forecasts have risen briskly, stocks have risen more. The S&P 500 stock index now trades at about 22 times the coming year's profits, according to FactSet, a level only exceeded at the peak of the dot-com boom in 2000.

Other asset markets are similarly stretched. Investors are willing to buy the bonds of junk-rated companies at the lowest yields since at least 1995, and the narrowest spread above safe Treasurys since 2007, according to Bloomberg Barclays data. Residential and commercial property prices, adjusted for inflation, are around the peak reached in 2006.

Stock and property valuations are more justifiable today than in 2000 or in 2006 because the returns on riskless Treasury bonds are so much lower. In that sense, the Fed's policies are working precisely as intended: improving both the economic outlook, which is good for profits, housing demand, and corporate creditworthiness; and the appetite for risk.

Nonetheless, low rates are no longer sufficient to justify some asset valuations. Instead, bulls invoke alternative metrics.

Bank of America recently noted companies with relatively low carbon emissions and higher water efficiency earn higher valuations. These valuations aren't the result of superior cash flow or profit prospects, but a tidal wave of funds invested according to environmental, social and governance, or ESG, criteria.

Conventional valuation is also useless for cryptocurrencies which earn no interest, rent or dividends. Instead, advocates claim digital currencies will displace the fiat currencies issued by central banks as a transaction medium and store of value. "Crypto has the potential to be as revolutionary and widely adopted as the internet," claims the prospectus of the initial public offering of crypto exchange Coinbase Global Inc., in language reminiscent of internet-related IPOs more than two decades earlier. Cryptocurrencies as of April 29 were worth more than $2 trillion, according to CoinDesk, an information service, roughly equivalent to all U.S. dollars in circulation.

Financial innovation is also at work, as it has been in past financial booms. Portfolio insurance, a strategy designed to hedge against market losses, amplified selling during the 1987 stock market crash. In the 1990s, internet stockbrokers fueled tech stocks and in the 2000s, subprime mortgage derivatives helped finance housing. The equivalent today are zero commission brokers such as Robinhood Markets Inc., fractional ownership and social media, all of which have empowered individual investors.

Such investors increasingly influence the overall market's direction, according to a recent report by the Bank for International Settlements, a consortium of the world's central banks. It found, for example, that since 2017 trading volume in exchange-traded funds that track the S&P 500, a favorite of institutional investors, has flattened while the volume in its component stocks, which individual investors prefer, has climbed. Individuals, it noted, are more likely to buy a company's shares for reasons unrelated to its underlying business -- because, for example, its name is similar to another stock that is on the rise.

While such speculation is often blamed on the Fed, drawing a direct line is difficult. Not so with fiscal stimulus. Jim Bianco, the head of financial research firm Bianco Research, said flows into exchange-traded funds and mutual funds jumped in March as the Treasury distributed $1,400 stimulus checks. "The first thing you do with your check is deposit it in your account and in 2021 that's your brokerage account," said Mr. Bianco.

Facing the future

It's impossible to predict how, or even whether, this all ends. It doesn't have to: High-priced stocks could eventually earn the profits necessary to justify today's valuations, especially with the economy's current head of steam. In he meantime, more extreme pockets of speculation may collapse under their own weight as profits disappoint or competition emerges.

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05-08-21 0014ET