Alan Greenspan, the influential former chairman of the U.S. Federal Reserve who presided over nearly two decades of economic growth and turmoil, died Monday at the age of 100 from complications related to Parkinson’s disease, his wife, NBC News correspondent Andrea Mitchell, said. Greenspan passed away at his home, leaving behind a profound and complex legacy as a central figure in American and global economic policy.

Greenspan served as Federal Reserve chairman from 1987 to 2006, appointed by President Ronald Reagan and confirmed by three subsequent presidents: George H.W. Bush, Bill Clinton, and George W. Bush. In this role, he steered the U.S. economy through numerous crises and periods of growth, including the 1987 stock market crash known as “Black Monday,” the 1990-91 recession, the Asian and Russian financial crises of the late 1990s, the dot-com bubble burst, and the economic aftermath of the Sept. 11 attacks.

During his tenure, Greenspan was widely regarded as an economic maestro, earning nicknames like “The Maestro” and “Oracle” for his perceived skill in managing monetary policy and his influence over markets. He was famous for his cryptic public statements, including his 1996 reference to “irrational exuberance” regarding overvalued asset prices, a phrase that became a hallmark of his era. Greenspan’s approach helped guide the longest economic expansion in U.S. history up to that point, characterized by low inflation, strong productivity gains—particularly from advances in technology—and unemployment rates that dipped below 4 percent.

However, Greenspan’s legacy has been deeply contested, especially in the aftermath of the 2008 financial crisis. Critics argue that his policies of keeping interest rates low after the 2001 recession contributed to the housing bubble that preceded the crisis. His steadfast faith in the self-regulating capacity of financial markets and a light regulatory touch, particularly regarding derivatives and mortgage lending, are seen by many as factors that left the economy vulnerable. In 2008, Greenspan admitted before Congress that he had made a mistake in assuming that banks would effectively police themselves.

Supporters emphasize that Greenspan operated in a complex and evolving economic landscape and credit him with preserving price stability and economic growth for many years. The Federal Reserve acknowledged his contributions to monetary policy and said he helped anchor public confidence in the institution during times of uncertainty. Greenspan’s impact on the Fed’s transparency was notable; he was the first chairman to issue post-meeting statements explaining interest rate decisions and began releasing meeting minutes and transcripts, increasing public insight into Fed policy.

Born in 1926 in Manhattan, Greenspan initially pursued a career in music, studying clarinet and saxophone and performing professionally before shifting to economics. He earned a doctorate from New York University and was a longtime economic consultant prior to his entry into government service, which included roles advising presidents Nixon, Ford, and Reagan. He was known for his analytical rigor, a penchant for quietly influencing policymakers, and a wit that often masked the complexity of his communications.

Greenspan’s personal life included a long partnership with Andrea Mitchell, whom he married in 1997 after a lengthy courtship. He was previously associated with the libertarian philosopher Ayn Rand and maintained a philosophy favoring limited government intervention in markets.

Upon his death, tributes acknowledged Greenspan as a towering figure in central banking who left an indelible mark on U.S. and global economic policy. His career reflected the tensions between economic optimism and the risks of deregulation that continue to shape debates on monetary policy and financial oversight.