From the given sentence, extract the phrase (often noun or verb) that carries the given relationship. The generated phrase should be present in the sentence.

Given Relationship: 'be chairman of', Sentence: 'The term was used by Alan Greenspan , chairman of the Federal Reserve Board , at a black-tie dinner speech in Washington on December 5 , 1996 .'

Show your work and conclude with the exact phrasing "Therefore, the final answer is [answer]." where [answer] is just the final number or expression that solves the problem.
user
chairman