Former Federal Reserve Chairman Alan Greenspan (R) appears by video conference as current Federal Reserve chair Janet Yellen, former Federal Reserve chairs Ben Bernanke, and Paul Volcker participate in a forum in New York, April 7, 2016. REUTERS/Kathy Willens/Pool TPX IMAGES OF THE DAY

U.S. Federal Reserve Chairman Ben Bernanke responds to reporters during his final planned news conference before his retirement, at the Federal Reserve Bank headquarters in Washington, December 18, 2013. The U.S. Federal Reserve announced plans to trim its aggressive bond-buying program on Wednesday but sought to temper the long-awaited move by suggesting its key interest rate would stay lower for even longer than previously promised. REUTERS/Jonathan Ernst (UNITED STATES - Tags: POLITICS BUSINESS TPX IMAGES OF THE DAY) 

U.S. Federal Reserve Chairman Ben Bernanke is reflected in a glass table top as he holds town hall event for teachers at the Federal Reserve Board's building in Washington November 13, 2013. REUTERS/Jonathan Ernst (UNITED STATES - Tags: POLITICS BUSINESS EDUCATION) 

Finance ministers and central bank governors from the G20 arrive for a family photo during the 2013 Spring Meeting of the International Monetary Fund and World Bank in Washington, April 19, 2013. Finance leaders from the Group of 20 nations on Friday reaffirmed a pledge that advanced countries will develop fiscal strategies by September to ensure the sustainability of their budgets. Seen (L-R) are Irish Finance Minister Michael Noonan, Brazil's Central Bank Governor Alexandre Tombini, U.S. Federal Reserve Chairman Ben Bernanke and Saudi Arabia's Minister of Finance Ibrahim Al-Assaf. REUTERS/Yuri Gripas (UNITED STATES - Tags: POLITICS BUSINESS TPX IMAGES OF THE DAY) 

Chairman of the U.S. Federal Reserve Ben Bernanke listens with his staff while he testifies before the House Committee on Financial Services while on Capitol Hill in Washington, February 27, 2013. REUTERS/Larry Downing (UNITED STATES - Tags: POLITICS BUSINESS) 

U.S. Federal Reserve Chairman Ben Bernanke is pictured before his testimony at a Joint Economic Committee hearing on economic outlook and policy on Capitol Hill in Washington June 7, 2012. REUTERS/Jason Reed (UNITED STATES - Tags: POLITICS BUSINESS) 

U.S. Federal Reserve Chairman Ben Bernanke speaks at a news conference following the monthly two-day meeting at the Federal Reserve in Washington, April 25, 2012. The Federal Reserve on Wednesday offered a modestly brighter assessment of the economy's prospects and few clues on the path of monetary policy, as it reiterated that interest rates likely will not rise until at least late 2014. REUTERS/Jason Reed (UNITED STATES - Tags: POLITICS BUSINESS TPX IMAGES OF THE DAY) 

U.S. Federal Reserve Chairman Ben Bernanke testifies before the House Budget committee hearing on the state of the Economy on Capitol Hill in Washington February 2, 2012. REUTERS/Yuri Gripas (UNITED STATES - Tags: POLITICS BUSINESS) 

U.S. Federal Reserve Chairman Ben Bernanke testifies before the House Budget committee hearing on the state of the Economy on Capitol Hill in Washington February 2, 2012. REUTERS/Yuri Gripas (UNITED STATES - Tags: POLITICS BUSINESS) 

U.S. Federal Reserve Chairman Ben Bernanke pauses during a news conference following a two-day policy session in Washington November 2, 2011. The Federal Reserve on Wednesday slashed its forecast for economic growth, raised projections for unemployment, and suggested Europe's debt crisis posed big downside risks to the U.S. economy. REUTERS/Jason Reed (UNITED STATES - Tags: POLITICS BUSINESS TPX IMAGES OF THE DAY PROFILE) 

U.S. Federal Reserve Chairman Ben Bernanke is pictured before testifying at a Joint Economic Committee hearing on the economic outlook, on Capitol Hill in Washington October 4, 2011. The Federal Reserve is prepared to take further steps to help a fragile economic recovery held back by a weak job market and financial stresses in Europe, Bernanke said on Tuesday. REUTERS/Jason Reed (UNITED STATES - Tags: POLITICS BUSINESS) 

Chairman of the Federal Reserve, Ben Bernanke, is seen making an address on a television screen among the trading information from the day's trading on the floor of the New York Stock Exchange in New York June 22, 2011. The Federal Reserve said the pace of economic recovery was proceeding more slowly than it had expected, but it expressed hope growth would pick up soon. REUTERS/Lucas Jackson (UNITED STATES - Tags: BUSINESS) 

U.S. Federal Reserve Chairman Ben Bernanke arrives to testify before a House Financial Services hearing on the "Monetary Policy and the State of the Economy" on Capitol Hill in Washington, July 22, 2010. REUTERS/Jim Young (UNITED STATES - Tags: POLITICS BUSINESS IMAGES OF THE DAY) 

U.S. Federal Reserve Chairman Ben Bernanke delivers a speech at the Italian Academy at Columbia University in New York, June 16, 2010.REUTERS/Keith Bedford (UNITED STATES - Tags: BUSINESS) 

U.S. Federal Reserve Chairman Ben Bernanke makes his way to deliver a speech at the Italian Academy at Columbia University in New York, June 16, 2010.REUTERS/Keith Bedford (UNITED STATES - Tags: BUSINESS) 

U.S. Federal Reserve Chairman Ben Bernanke prepares to testify to the House Budget Committee on Capitol Hill in Washington June 9, 2010. REUTERS/Joshua Roberts (UNITED STATES - Tags: POLITICS BUSINESS) 

U.S. Chairman of the Federal Reserve Ben Bernanke takes part in an interview at the Woodrow Wilson Center Board and Council's dinner at the Ronald Reagan Building and International Trade Center in Washington, June 7, 2010. REUTERS/Jim Young (UNITED STATES - Tags: POLITICS BUSINESS) 

U.S. Federal Reserve Chairman Ben Bernanke attends a conference hosted by the Bank of Japan in Tokyo May 26, 2010. U.S. inflation expectations were very stable and well-anchored at a low level despite pronounced swings in the past few years, Bernanke said on Wednesday. REUTERS/Yuriko Nakao (JAPAN - Tags: BUSINESS POLITICS) 

U.S. Federal Reserve Chairman Ben Bernanke holds a folder containing a copy of his remarks that he is to deliver at the inaugural meeting of the National Commission on Fiscal Responsibility and Reform in Washington April 27, 2010. Bernanke said on Tuesday the country's budget deficit is on an unsustainable path and requires near-term action from policymakers to avoid dangerous outcomes. REUTERS/Jason Reed (UNITED STATES - Tags: BUSINESS POLITICS IMAGES OF THE DAY) 

U.S. Federal Reserve Chairman Ben Bernanke prepares to deliver remarks at the inaugural meeting of the National Commission on Fiscal Responsibility and Reform in Washington April 27, 2010. REUTERS/Jason Reed (UNITED STATES - Tags: BUSINESS) 

U.S. Treasury Secretary Timothy Geithner (L) and Federal Reserve Chairman Ben Bernanke leave a ceremony to debut the new design for the US$100 note at the Department of the Treasury in Washington, April 21, 2010. Officials from the U.S. Department of the Treasury, the Board of Governors of the Federal Reserve System and the United States Secret Service today unveiled the new design for the $100 note. Complete with advanced technology to combat counterfeiting, the new design for the $100 note retains the traditional look of U.S. currency. REUTERS/Jim Young (UNITED STATES - Tags: POLITICS BUSINESS) 

Chairman of the Federal Reserve Ben Bernanke testifies before the Joint Economic Committee on Capitol Hill in Washington April 14, 2010. REUTERS/Kevin Lamarque (UNITED STATES - Tags: POLITICS BUSINESS) 

Chairman of the Federal Reserve Ben Bernanke testifies before the Joint Economic Committee on Capitol Hill in Washington April 14, 2010. REUTERS/Kevin Lamarque (UNITED STATES - Tags: POLITICS BUSINESS) 

U.S. Federal Reserve Chairman Ben Bernanke prepares to speak at the December luncheon meeting of the Economic Club of Washington, December 7, 2009. REUTERS/Jason Reed (UNITED STATES BUSINESS IMAGES OF THE DAY) 

U.S. Federal Reserve Chairman Ben Bernanke prepares to speak at the December luncheon meeting of the Economic Club of Washington, December 7, 2009. REUTERS/Jason Reed (UNITED STATES BUSINESS) 

U.S. Chairman of the Federal Reserve Ben Bernanke listens to questions after making remarks about a year of economic turmoil at the Brookings Institution in Washington September 15, 2009. REUTERS/Jim Young (UNITED STATES BUSINESS POLITICS IMAGES OF THE DAY) 

U.S. Federal Reserve Chairman, Ben Bernanke (L), French finance minister, Christine Lagarde (C) and U.S. Treasury Secretary Timothy Geithner, return to a meeting after a group photograph at the G20 Finance Ministers meeting at the Treasury, in central London September 5, 2009. G20 finance leaders pledged on Saturday to keep economic life-support packages in place for now, slap tighter controls on bankers' pay and give a bigger voice to emerging markets in the international institutions. REUTERS/Lefteris Pitarakis/Pool (BRITAIN BUSINESS POLITICS) 

Chairman of the Federal Reserve Ben Bernanke testifies before the Senate Banking, Housing and Urban Affairs Committee on Capitol Hill in Washington July 22, 2009. REUTERS/Kevin Lamarque (UNITED STATES POLITICS BUSINESS IMAGES OF THE DAY) 

Federal Reserve Chairman Ben Bernanke speaks via satellite to the Federal Reserve Bank of Chicago Conference on Bank Structure and Competition May 7, 2009. REUTERS/John Gress (UNITED STATES BUSINESS POLITICS IMAGES OF THE DAY) 

Federal Reserve Chairman Ben Bernanke (R) listens next to U.S. Treasury Secretary Timothy Geithner while appearing before the House Financial Services Committee Hearing on "Oversight of the Federal Government's Intervention at American International Group (AIG)," on Capitol Hill in Washington March 24, 2009. REUTERS/Kevin Lamarque (UNITED STATES BUSINESS POLITICS IMAGE OF THE DAY TOP PICTURE) 

U.S. Federal Reserve Chairman Ben Bernanke testifies before the Senate Budget Committee on Capitol Hill in Washington March 3, 2009. Bernanke on Tuesday urged bold action action to pull the economy out of a deepening slump, even if it means a surge in U.S. government debt. REUTERS/Kevin Lamarque (UNITED STATES) 

US Federal Reserve Chairman Ben Bernanke sits for testimony before the Senate Banking, Housing and Urban Affairs Committee on Capitol Hill in Washington, February 24, 2009. REUTERS/Jonathan Ernst (UNITED STATES) 

US Federal Reserve Chairman Ben Bernanke listens to a question as he testifies before the Senate Banking, Housing and Urban Affairs Committee on Capitol Hill in Washington, February 24, 2009. REUTERS/Jonathan Ernst (UNITED STATES) 

US Federal Reserve Chairman Ben Bernanke (R) waits to deliver remarks at a luncheon at the National Press Club in Washington, February 18, 2009. REUTERS/Jonathan Ernst (UNITED STATES) 

U.S. Federal Reserve Bank Chairman Ben Bernanke listens to questions after delivering his speech at the London School of Economics in central London January 13, 2009. REUTERS/Toby Melville (BRITAIN) 

US Federal Reserve Bank Chairman Ben Bernanke is seen through a backdrop of doors as he addresses housing issues at a home ownership and mortgage conference at the Federal Reserve in Washington, December 4, 2008. REUTERS/Jonathan Ernst (UNITED STATES) 

U.S. Treasury Secretary Henry Paulson (L) and Federal Reserve Chairman Ben Bernanke prepare to testify at the House Financial Services Committee hearing on "Oversight of Implementation of the Emergency Economic Stabilization Act of 2008 and of Government Lending and Insurance Facilities; Impact on Economy and Credit Availability" on Capitol Hill in Washington November 18, 2008.
REUTERS/Kevin Lamarque (UNITED STATES) 

U.S. Treasury Secretary Henry Paulson (L) and Federal Reserve Chairman Ben Bernanke arrive to testify at the House Financial Services Committee hearing on "Oversight of Implementation of the Emergency Economic Stabilization Act of 2008 and of Government Lending and Insurance Facilities; Impact on Economy and Credit Availability" on Capitol Hill in Washington November 18, 2008. REUTERS/Kevin Lamarque (UNITED STATES) 

U.S. Speaker of the House Nancy Pelosi (2nd R) and Rep. Barney Frank (R) (D-MA) meet with Federal Reserve Chairman Ben Bernanke (L) and Treasury Secretary Henry Paulson (2nd L) in the Capitol in Washington November 17, 2008.
REUTERS/Kevin Lamarque (UNITED STATES) 

U.S. Federal Reserve President Ben Bernanke delivers his speech at the fifth European Central Banking Conference in Frankfurt, November 14, 2008. REUTERS/Kai Pfaffenbach (GERMANY)) 

U.S. Federal Reserve Chairman Ben Bernanke participates in a House hearing on "Economic Recovery - Options and Challenges" on Capitol Hill in Washington, October 20, 2008. REUTERS/Jason Reed (UNITED STATES) 

U.S. Federal Reserve Chairman Ben Bernanke participates in a House hearing on "Economic Recovery - Options and Challenges" on Capitol Hill in Washington, October 20, 2008. REUTERS/Jason Reed (UNITED STATES) 

Federal Reserve Chairman Ben Bernanke addresses the Economic Club of New York regarding financial markets in New York, October 15, 2008. Bernanke said on Wednesday the goal of a U.S. government plan to bail out financial institutions by buying their bad assets would be to restore liquidity to the market. REUTERS/Lucas Jackson (UNITED STATES) 

U.S. Treasury Secretary Henry Paulson looks over his entourage after announcing that the Treasury Department will take equity stakes in potentially thousands of banks totaling about $250 billion at the Treasury Department Cash Room in Washington, October 14, 2008. Standing besides Paulson, (2nd L-R): Federal Reserve Chairman Ben Bernanke, President and CEO of the Federal Reserve Bank of New York Timothy F. Geithner, OCC Comptroller John Duggan and SEC Chairman Christopher Cox. REUTERS/Hyungwon Kang (UNITED STATES) 

(L-R) Federal Reserve Chairman Ben Bernanke, Italy's Central Bank Governor Mario Draghi, Bank of England Governor Mervyn King, Bank of Japan Governor Masaaki Shirakawa and Britain's Finance Minister Alistair Darling gather for the group photo of the G7 Finance Ministers and Central Bank Governors Ministerial after their meeting at the Treasury Department in Washington October 10, 2008. REUTERS/Yuri Gripas (UNITED STATES) 

U.S. Federal Reserve Chairman Ben Bernanke pauses during a speech to the National Association for Business Economics (NABE) about the current state of the economy in Washington, October 7, 2008. Bernanke said recent economic data and financial developments showed that the outlook for growth had worsened while the outlook for inflation to ease had improved.
REUTERS/Mitch Dumke (UNITED STATES) 

U.S. Treasury Secretary Henry Paulson and Chairman of the Federal Reserve Ben Bernanke testify before the House Financial Services Committee about credit market turmoil and the government economic bailout on Capitol Hill in Washington September 24, 2008. REUTERS/Kevin Lamarque (UNITED STATES) 

Chairman of the Federal Reserve Ben Bernanke testifies before the Joint Economic Committee about credit market turmoil and the government economic bailout on Capitol Hill in Washington September 24, 2008. REUTERS/Kevin Lamarque (UNITED STATES) 

U.S. Treasury Secretary Henry Paulson (L) and Chairman of the Federal Reserve Ben Bernanke (R) testify before the House Financial Services Committee about credit market turmoil and the government economic bailout on Capitol Hill in Washington September 24, 2008.
REUTERS/Kevin Lamarque (UNITED STATES) 

U.S. Treasury Secretary Henry Paulson (L), Federal Reserve Chairman Ben Bernanke (C) and Securities and Exchange Commission Chairman Christopher Cox testify before the Senate Banking Committee on Capitol Hill in Washington September 23, 2008. REUTERS/Larry Downing (UNITED STATES) 

U.S. Federal Reserve Chairman Ben Bernanke pauses during remarks at the 2008 National Historically Black Colleges and Universities Week Conference in Washington September 9, 2008. Bernanke on Tuesday praised historically black colleges and universities for their roles in education, but made no comments about the recent government rescue of mortgage finance companies Fannie Mae and Freddie Mac. REUTERS/Jason Reed (UNITED STATES) 

U.S. Federal Reserve Chairman Ben Bernanke leaves with his security detail after speaking at the 2008 National Historically Black Colleges and Universities Week Conference in Washington September 9, 2008. Bernanke on Tuesday praised historically black colleges and universities for their roles in education, but made no comments about the recent government rescue of mortgage finance companies Fannie Mae and Freddie Mac. REUTERS/Jason Reed (UNITED STATES) 

Chairman of the Federal Reserve Ben Bernanke testifies before the U.S. House Financial Services Committee on Capitol Hill in Washington July 16, 2008. REUTERS/Larry Downing (UNITED STATES) 

Chairman of the Federal Reserve Ben Bernanke reports his Monetary Policy Report before the U.S. Senate Banking Committee on Capitol Hill in Washington, July 15, 2008. Restoring financial market stability is a top priority for the U.S. Federal Reserve as a weakening housing market, tighter credit and rising oil prices threaten the economy, Bernanke said on Tuesday. REUTERS/Larry Downing (UNITED STATES) 

Chairman of the Federal Reserve Ben Bernanke is pictured moments before he reports his Monetary Policy Report before the U.S. Senate Banking Committee on Capitol Hill in Washington, July 15, 2008. Restoring financial market stability is a top priority for the U.S. Federal Reserve as a weakening housing market, tighter credit and rising oil prices threaten the economy, Bernanke said on Tuesday. REUTERS/Larry Downing (UNITED STATES)