Greenspan Penned ‘Irrational Exuberance’ 30 Years Ago. It Aged Well.

Longstanding Federal Reserve Chairman Alan Greenspan passed away Monday at age 100. But for those of us old enough to remember the dot-com boom, his legacy looms large.

During his tenure as chair from 1987 to 2006, Greenspan was renowned for his cryptic utterances on the economy, leaving rate-watchers befuddled as to whether they presaged a likely cut or hike. His wife, veteran NBC correspondent Andrea Mitchell, famously quipped that their marriage took time because “he claims he proposed three times before I was able to understand. He was so oblique. It was like his testimony.”

In spite of his long history of obfuscation, however, Greenspan is best known for a fairly unambiguous two-word phrase: “irrational exuberance.” He coined it in a 1996 speech to the  American Enterprise Institute, a conservative-leaning think tank, titled “The Challenge of Central Banking in a Democratic Society.”

One of the speech’s core points was the notion that pricing logic in an industrial economy dominated by durable goods and materials is far simpler than for a modern economy increasingly dominated by software and services.

“What is the price of a unit of software or a legal opinion? How does one evaluate the price change of a cataract operation over a 10-year period when the nature of the procedure and its impact on the patient changes so radically?” he mused, before turning to that most famous insight.

That insight, if I am translating Greenspan-speak correctly, was linked to the question of how one can establish long-term confidence in valuations of assets tied to fast-changing technologies and business models, like software, where prior notions of unit economics no longer applied.

“How do we know when irrational exuberance has unduly escalated asset values, which then become subject to unexpected and prolonged contractions,” he wondered. It’s a conjecture that 30 years later still has no obvious answer.

Notably, Greenspan’s speech actually predated the most heated periods of the dot-com boom, bubble and implosion, which began in the late 1990s and culminated with the Nasdaq hitting its cyclical peak in early 2000. During and shortly after that period, money-losing e-commerce companies like online grocer Webvan and pet supply retailer Pets.com famously went public at then sky-high valuations before abruptly shuttering. Internet infrastructure providers fared even worse, exemplified by networking equipment maker Nortel Networks going from Canada’s most valuable company to penny stock in a couple years.

But while losers lost big, winners eventually eclipsed them. Dot-com-era megastars Google and Amazon, for instance, are now worth nearly $8 trillion combined.

That brings us to one of Greenspan’s other well-known analogies: the lottery ticket.

In Congressional testimony in early 1999, pressed for his thoughts on then fast-rising share prices of hot internet companies, the Fed chair compared the stock-buying frenzy to playing the lottery. He observed that people have long been willing to pay more for a lottery ticket than their chances of winning would justify, simply because they are drawn to the remote chance of a huge win.

”And undoubtedly some of these small companies, which have stock prices going through the roof, will succeed and they very well may justify even higher prices,” he said. ”The vast majority are almost sure to fail. That’s the way the markets work in this regard.”

Fast-forward to today, and one is easily drawn to apply Greenspan’s analogy to the current AI mania. Once again, we’re seeing unprecedented valuations attached to money-losing companies, many in still relatively nascent stages of development.

In other ways, however, this time it’s not a dot-com lottery ticket redo. For one thing, the companies in which a retail investor might be buying said ticket are by no means small. SpaceX, at its current market cap, is the sixth-most valuable U.S. public company. It’s priced like a winner, not a wanna-be.

Same holds true for recent valuations for Anthropic and OpenAI, both of which have confidentially filed for public offerings likely to debut in coming months. Anthropic hit a $965 billion post-money valuation, while OpenAI’s was recently around $852 billion.

One wonders what Greenspan would say about these stratospheric asset price levels. I’d suspect there are better than lottery-ticket odds that it would be something cryptic.

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Photo: Dr. Alan Greenspan, former Chairman of the Board of Governors of the Federal Reserve, speaks at the Per Jacobsson Foundation Lecture, October 21, 2007, in Washington, DC. (Photo by International Monetary Fund Photograph/Stephen Jaffe used under the Creative Commons Deed – Attribution 4.0 International.)

Illustration: Dom Guzman