WASHINGTON (AP) — Former U.S. Federal Reserve Chair Alan Greenspan died Monday from complications of Parkinson's disease, said his wife of 29 years, NBC News correspondent Andrea Mitchell. He was 100.

"To me he was my husband, who shaped my life from our very first date in 1984," Mitchell said. "He had 'irrational exuberance' for baseball, the Washington Commanders, tennis, golf, and music, especially jazz. He will be remembered for his brilliance and his kindness. Being his life partner was the joy of my life."

In his 18½ years at the helm of the Fed, Greenspan presided over a sustained era of American growth and prosperity, yet one that ended with devastating consequences in 2008, two years after he had left the central bank.

Era of U.S. economic growth

Greenspan was so respected during his many years as head of the world's most influential central bank that by the time he stepped down in 2006, he was widely celebrated as the "Oracle" and "Maestro."

He presided over a breathtaking surge in stock prices and a 10-year economic boom that began in March 1991. He was widely celebrated as a virtuoso who nurtured America's economic well-being and whose nearly every utterance was parsed for clues as to where interest rates, the economy and the financial markets might be headed.

The intense scrutiny of Greenspan's intentions gave birth to new Fed folklore: The "Briefcase Indicator." A stuffed briefcase carried into Fed meetings implied changes might be afoot because Greenspan carried with him charts and research to make his point.

"Under his leadership, the Federal Reserve achieved a sustained era of price stability that supported economic growth and helped anchor the public's confidence in the institution," the Fed said in a statement Monday. "He brought rigorous analytical discipline to monetary policymaking and helped establish the credibility that remains one of the Federal Reserve's most important assets."

U.S. housing crisis raised questions about policies

Greenspan's reputation suffered a serious setback, however, soon after he left the Fed in 2006. The American housing market collapsed, igniting a global financial crisis that nearly toppled the U.S. banking system and plunged the economy into the worst recession since the 1930s.

Critics pinned much of the blame for the crisis on Greenspan's easy-money policies and on what they believed was an overexuberant faith in lightly supervised financial markets.

Greenspan himself later acknowledged that "I made a mistake" in assuming the nation's banks, whose stability undergirds the financial system and the entire economy, could essentially regulate themselves.

As housing values plummeted, millions of Americans, many of them stuck with outsize mortgage debt, lost homes to foreclosure. The spiraling financial crisis sent the U.S. economy sinking into the Great Recession of 2007-2009.

The crisis in the U.S. rapidly spread overseas, leading to a debt crisis for nations in Europe. China also engineered a massive government stimulus package to stabilize its economy.

Greenspan became the authoritative voice on the U.S. economy

Until then, however, it seemed that Greenspan could do no wrong. Not only in the United States but across the world, he was regarded with a mixture of reverence and awe. Many openly dreaded the day when he would leave the Fed.

Investors hung on his sometimes inscrutable observations. In the most well-known such remark, Greenspan sent financial markets reeling on Dec. 5, 1996, when he suggested with just two words — "irrational exuberance" — that stock prices were too high.

Mindful of his power to move markets, Greenspan typically resorted to obfuscation. At times, he even satirized his habit of doing so.

"I know you believe you understand what you think I said, but I am not sure you realize that what you heard is not what I meant," Greenspan once told a befuddled congressional committee.

A protégé is born

Born in the Washington Heights neighborhood of Manhattan, the young Greenspan was a math whiz who was trotted out by his mother to show off for visitors.

"I was a prop at parties," he said in a 2007 interview with PBS News Hour. A Julliard School dropout, he worked as a professional musician in his teens, playing clarinet and saxophone alongside the future jazz great Stan Getz — a humbling experience that persuaded the young Greenspan to seek another line of work.

He pursued undergraduate and graduate study in economics at New York University, eventually earning a doctorate there. For most of three decades, he ran an economic consulting firm. During the 1950s, he became a disciple of the libertarian philosopher Ayn Rand, who stuck him with the nickname the "Undertaker'' for his dark clothes and quiet bearing. When Greenspan was sworn in as President Gerald Ford's chief economic adviser in 1974, Rand stood beside him.

An early trial for a new Fed chair

President Ronald Reagan tapped Greenspan to run the Fed in 1987. He was tested almost immediately. On Oct. 19, 1987, which came to be known as "Black Monday," the stock market suffered the worst one-day percentage loss in American history just two months into his term. The Dow Jones Industrial Average shed 22.6% of its value rapidly for reasons that weren't entirely clear then, and remain opaque to this day.

Greenspan won credit for helping restore calm and stability. He assured Wall Street that the Fed would supply as much money to the financial system as was needed to restore calm. Stocks recovered, and the American economy emerged unscathed by the market crash.

Greenspan's crisis management skills were tested again in 1997 and 1998, when a financial crisis in Asia threatened to spread economic devastation around the globe. Under Greenspan, the Fed arranged an emergency loan to Thailand and persuaded U.S. banks to roll over short-term loans to a teetering South Korea.

During his tenure at the Fed, Greenspan drew praise for presiding over what was at the time the longest economic expansion in American history. Over that time, the nation's unemployment rate briefly dropped below 4% for the first time since 1970.

And inflation, which had bedeviled the United States and much of the global economy during the 1970s, was remarkably dormant during Greenspan's chairmanship, something many economists had not thought could occur for so long a period.

During the long boom, Greenspan argued that improvements in technology had made the economy so efficient that it could run faster, at lower rates of unemployment, without unleashing inflation. As a consequence, the theory went, the Fed could keep interest rates low even when the economy was roaring.

A passion for numbers and life

As Fed chair, Greenspan relished poring over obscure economic data, from monthly boxcar loadings to steel production, all in a bid to assess where the economy was going. He would often phone economists at other government agencies to discuss details. He would rise early each morning for a two-hour soak in his bathtub, time that he used to review statistics and Fed staff memos.

Improbably, Greenspan also made the gossip pages as something of an unlikely ladies' man. He dated the television journalist Barbara Walters and later married Mitchell after a 12-year courtship. They had no children.

Greenspan had dated Walters while working as an adviser to President Gerald Ford. According to a biography of Greenspan, "The Man Who Knew" by Sebastian Mallaby, when Ford read a newspaper item about the pair, he cut it out and sent it to his chief of staff, Dick Cheney, with a note that said, "I don't believe it."

A strong faith in self-regulating markets is challenged

All along, Greenspan held fast to the belief that financial markets could largely regulate themselves. With officials from President Bill Clinton's White House, he helped block efforts by Brooksley Born, the nation's top commodities regulator, to bring federal oversight in the late 1990s to the shadowy market in over-the-counter derivatives. The derivatives allowed speculators to make bets on everything from the price of oil to high-risk mortgages.

Eventually, history would vindicate Born, not the Maestro.

The low interest rates Greenspan had engineered helped swell housing prices into a dangerous bubble. And the financial deregulation he supported allowed banks and other financial firms to pile up huge risks, often hidden from government supervision. Bad derivatives bets helped sink insurance giant American International Group, which required a $180 billion taxpayer bailout.

The Financial Crisis Inquiry Commission, which was assigned to investigate the debacle by Congress, concluded:

"More than 30 years of deregulation and reliance on self-regulation by financial institutions, championed by former Federal Reserve chairman Alan Greenspan and others ... had stripped away key safeguards, which could have helped avoid catastrophe."

Life after the Fed

In the years after stepping down as Fed chairman in 2006 just shy of his 80th birthday, Greenspan kept busy doing what he loved to do most — following the economic data. He ran his own consulting firm, Greenspan Associates, through which he dispensed advice to Wall Street clients and collected handsome speaking fees.

He kept up a busy schedule well into his 90s, writing his memoir and two other books on the economy, as well as opining on the latest economic developments on television news shows.

He also signed onto opinion articles and statements defending the Federal Reserve's political independence from President Donald Trump's ongoing attacks. In January 2026 he signed a statement criticizing the Trump administration's investigation of Fed Chair Jerome Powell. The statement, which was also signed by two other former Fed chairs and five former Treasury secretaries, called the investigation "an unprecedented attempt to use prosecutorial attacks to undermine" the Fed's independence and warned it would have "highly negative consequences for inflation."

Greenspan's tenure as Fed chairman — from August 1987 through January 2006 — was just five months shy of the longest Fed chairman's tenure. That distinction belonged to William McChesney Martin, who served from 1951 until early 1970.

In his 2013 book "The Map and the Territory,'' Greenspan defended himself against critics who assigned him significant blame for the 2008 financial meltdown. He argued that traditional economic forecasting was no match for the irrational risk-taking that can feed catastrophic price bubbles.

"Bubbles go up very slowly as euphoria builds," Greenspan said in a 2013 interview with The Associated Press. "Then fear hits, and it comes down very sharply. When I started to look at that, I was sort of intellectually shocked."

AP Economics Writers Christopher Rugaber and Martin Crutsinger contributed to this report.