Alan Greenspan, the longest-serving Federal Reserve chairman in the modern era and one of the most influential economic policymakers of the twentieth century, died on Monday at the age of 100. His wife, NBC News chief Washington correspondent Andrea Mitchell, confirmed that he died at home from complications of Parkinson's disease. In a statement, she described him as "a giant of a man who helped shape the US economy for decades under presidents of both parties, but was always honest in acknowledging his mistakes."

Greenspan served as chairman of the Federal Reserve — the United States' central bank, which sets interest rates and oversees monetary policy — for nearly two decades, from August 1987 to January 2006, spanning the administrations of four presidents: Ronald Reagan, George H.W. Bush, Bill Clinton and George W. Bush. Often described as the second most powerful person in the country after the president, he presided over what became the longest economic expansion in US history, a decade of uninterrupted growth from 1991 to 2001. His instinct in the mid-1990s that a surge in productivity would keep inflation in check — allowing the economy to run hot without raising rates — earned him near-mythical status in financial circles. The Federal Reserve, in a statement marking his passing, said his contributions to monetary policy "left a lasting mark on this institution, on the broader field of economics, and on the country." His successor, Ben Bernanke, called him "a great central banker who helped lead his country through almost two decades of prosperity."

Born on 6 March 1926 in the Washington Heights neighbourhood of New York City, Greenspan showed an early talent for mathematics before pursuing a first career in music, studying clarinet at the renowned Juilliard School and playing in jazz bands before eventually turning to economics at New York University. His intellectual direction was shaped in part by his close association with the novelist and philosopher Ayn Rand, author of Atlas Shrugged and The Fountainhead, who championed free markets and individual self-interest over government intervention. Greenspan entered public life as an adviser to Richard Nixon's 1968 presidential campaign and later chaired the Council of Economic Advisers under Gerald Ford. His famous communication style — deliberately opaque and circular, often described as "Fed speak" — became almost as well known as his policy decisions. "I've learned a new language called Fed speak," he once quipped. "We learn to mumble with great incoherence."

His tenure was not without controversy. Greenspan won early praise for his swift response to the Black Monday stock market crash of October 1987, when the Dow Jones Industrial Average fell 22.6% in a single day — still the largest one-day percentage drop in history — by affirming the Fed's readiness to provide liquidity and cutting short-term interest rates. He steered the economy through multiple crises, including the 1997 Asian financial crisis, the 1998 Russian debt default and the turbulence following the September 11, 2001, attacks. Yet critics, including Nobel laureate Paul Krugman, argued that his persistent reliance on low interest rates inflated successive asset bubbles. His famous coinage "irrational exuberance" — used in a 1996 speech to warn of an overheating stock market — was later seen as an early sign he recognised the dangers he nonetheless failed to prevent. When the US housing bubble burst in 2007–2008, triggering the worst global financial crisis since the Great Depression, Greenspan's reputation suffered a dramatic reversal. Testifying before Congress in 2008, he acknowledged being "shocked" to discover that bankers' self-interest had not, as he had believed, protected their institutions from reckless risk-taking.

In later life Greenspan remained publicly engaged, writing a bestselling memoir, The Age of Turbulence, and continuing to comment on economic affairs. In January 2026, just months before his death, he joined a group of former senior Fed and Treasury officials in denouncing what they saw as politically motivated interference with the Federal Reserve's independence. His legacy, as one former Fed official put it, resists easy summary: "The deification that came just before the financial crisis was never really deserved, and the lambasting he took after he left was never fully deserved either."