Alan Greenspan, the 13th Chairman of the Federal Reserve who steered U.S. monetary policy through boom and crisis for nearly two decades, died Monday at his home from complications of Parkinson's disease. He was 100. His wife of 29 years, NBC News correspondent Andrea Mitchell, confirmed the news.

Greenspan served five terms as Fed chairman under four presidents — Ronald Reagan, George H.W. Bush, Bill Clinton, and George W. Bush — from 1987 to 2006. His 18.5-year tenure is the second longest in the central bank's history. He helped stabilize markets after the Black Monday crash of 1987, guided the economy through the 1997–98 Asian financial crisis, the dot-com bust, and post-9/11 turbulence.

His legacy remains contested. Praised for presiding over the longest U.S. economic expansion in history (1991–2001), he was later criticized for championing financial deregulation and low interest rates — policies many economists blame for the 2007–08 global financial crisis. Greenspan himself acknowledged in congressional testimony: "I made a mistake" in believing banks could adequately self-regulate. The Federal Reserve said Monday it "notes with deep sadness" his passing, calling his contributions "a lasting mark on this institution, on the broader field of economics, and on the country."