15- Alan Greenspan

Born in March 6, 1926, he is an american economist who served as chairman of the federal reserve of the USA from 1987-2006.He obtained a phd from New york university in 1977 for economics. He currently works as an advisor and provides consulting firms through his company, Greenspan Associates LLC. First appointed by president Ronald Reagan in August of 1987. He was reappointed at successive four-year intervals until retiring on January 31, 2006.