A screen displays the Dow Jones Industrial Average after the close of trading on the floor at the New York Stock Exchange (NYSE) in New York, U.S., June 4, 2019. REUTERS/Brendan McDermid 

A screen tracks the Dow Jones Industrial average during the trading day on the floor at the New York Stock Exchange (NYSE) in New York, U.S., May 29, 2019. REUTERS/Brendan McDermid 

A screen displays the Dow Jones Industrial Average after the close of trading on the floor of the New York Stock Exchange (NYSE) in New York, U.S., April 13, 2019. REUTERS/Brendan McDermid 

A screen displays the Dow Jones Industrial Average after the close of trading on the floor of the New York Stock Exchange (NYSE) in New York, U.S., April 13, 2019. REUTERS/Brendan McDermid 

A screen displays a chart of the Dow Jones Industrial Average on the floor of the New York Stock Exchange (NYSE) in New York, U.S., May 9, 2019. REUTERS/Brendan McDermid 

A screen displays a chart of the Dow Jones Industrial Average during trading on the floor of the New York Stock Exchange (NYSE) in New York, U.S., April 9, 2019. REUTERS/Brendan McDermid 

A screen displays a chart of the Dow Jones Industrial Average during trading on the floor of the New York Stock Exchange (NYSE) in New York, U.S., April 4, 2019. REUTERS/Brendan McDermid 

A screen displays the Dow Jones Industrial Average after the closing bell on the floor of the New York Stock Exchange (NYSE) in New York, U.S., March 20, 2019. REUTERS/Brendan McDermid 

A screen displays a chart of the Dow Jones Industrial Average during trading on the floor of the New York Stock Exchange (NYSE) in New York, U.S., March 22, 2019. REUTERS/Brendan McDermid 

A screen displays a chart of the Dow Jones Industrial Average during trading on the floor of the New York Stock Exchange (NYSE) in New York, U.S., March 20, 2019. REUTERS/Brendan McDermid 

A screen displays a chart of the Dow Jones Industrial Average during trading on the floor of the New York Stock Exchange (NYSE) in New York, U.S., March 7, 2019. REUTERS/Brendan McDermid 

A screen displays a chart of the Dow Jones Industrial Average during trading on the floor of the New York Stock Exchange (NYSE) in New York, U.S., March 4, 2019. REUTERS/Brendan McDermid 

A screen displays a chart of the Dow Jones Industrial Average during trading on the floor of the New York Stock Exchange (NYSE) in New York, U.S., February 27, 2019. REUTERS/Brendan McDermid 

A screen displays a chart tracking the Dow Jones Industrial Average during the trading day on the floor of the New York Stock Exchange (NYSE) in New York, U.S., February 8, 2019. REUTERS/Brendan McDermid 

A screen displays the Dow Jones Industrial Average following the close of trading on the floor of the New York Stock Exchange (NYSE) in New York, U.S., January 22, 2019. REUTERS/Brendan McDermid 

A screen displays a chart of the Dow Jones Industrial Average after the close of trading on the floor of the of the New York Stock Exchange (NYSE) in New York, U.S., January 22, 2019. REUTERS/Brendan McDermid 

A screen displays a chart of the Dow Jones Industrial Average after the close of trading on the floor of the New York Stock Exchange (NYSE) in New York, U.S., January 22, 2019. REUTERS/Brendan McDermid 

A screen displays the Dow Jones Industrial Average following the close of trading on the floor of the New York Stock Exchange (NYSE) in New York, U.S., January 22, 2019. REUTERS/Brendan McDermid 

A man walks past electronic boards showing Nikkei average (L) and the Dow Jones Industrial Average outside a brokerage in Tokyo, Japan, January 4, 2019. REUTERS/Kim Kyung-Hoon 

A screen displays the Dow Jones Industrial Average after the close of trading on the floor of the New York Stock Exchange (NYSE) in New York City, U.S., December 28, 2018. REUTERS/Jeenah Moon 

A screen displays the Dow Jones Industrial Average after the close of trading on the floor of the New York Stock Exchange (NYSE) in New York City, U.S., December 28, 2018. REUTERS/Jeenah Moon 

A screen displays the Dow Jones Industrial Average after the close of trading on the floor of the New York Stock Exchange (NYSE) in New York City, U.S., December 28, 2018. REUTERS/Jeenah Moon 

A screen displays the Dow Jones Industrial Average after the close of trading on the floor of the New York Stock Exchange (NYSE) in New York City, U.S., December 28, 2018. REUTERS/Jeenah Moon 

A screen displays the Dow Jones Industrial Average after the close of trading on the floor of the New York Stock Exchange (NYSE) in New York City, U.S., December 27, 2018. REUTERS/Eduardo Munoz 

A screen displays the Dow Jones Industrial Average after the close of trading on the floor of the New York Stock Exchange (NYSE) in New York City, U.S., December 26, 2018. REUTERS/Jeenah Moon 

A screen displays the Dow Jones Industrial Average after the close of trading on the floor of the New York Stock Exchange (NYSE) in New York City, U.S., December 26, 2018. REUTERS/Jeenah Moon OK? 

A screen displays the Dow Jones Industrial Average after the close of trading on the floor of the New York Stock Exchange (NYSE) in New York City, U.S., December 26, 2018. REUTERS/Jeenah Moon 

A screen displays the Dow Jones Industrial Average after the close of trading on the floor of the New York Stock Exchange (NYSE) in New York City, U.S., December 26, 2018. REUTERS/Jeenah Moon 

A screen displays the Dow Jones Industrial Average after the close of trading on the floor of the New York Stock Exchange (NYSE) in New York City, U.S., December 26, 2018. REUTERS/Jeenah Moon 

A screen displays the Dow Jones Industrial Average after the close of trading on the floor of the New York Stock Exchange (NYSE) in New York City, U.S., December 26, 2018. REUTERS/Jeenah Moon 

A screen displays the Dow Jones Industrial Average after the close of trading on the floor of the New York Stock Exchange (NYSE) in New York City, U.S., December 26, 2018. REUTERS/Jeenah Moon 

A screen displays the Dow Jones Industrial Average after the close of trading on the floor of the New York Stock Exchange (NYSE) in New York City, U.S., December 26, 2018. REUTERS/Jeenah Moon 

A screen displays the Dow Jones Industrial Average after the close of trading on the floor of the New York Stock Exchange (NYSE) in New York City, U.S., December 26, 2018. REUTERS/Jeenah Moon 

A screen displays the Dow Jones Industrial Average after the close of trading on the floor of the New York Stock Exchange (NYSE) in New York City, U.S., December 26, 2018. REUTERS/Jeenah Moon 

A screen displays a chart of the Dow Jones Industrial Average after the close of trading on the floor of the New York Stock Exchange (NYSE) in New York City, U.S., December 20, 2018. REUTERS/Brendan McDermid 

A screen displays the Dow Jones Industrial Average after the close of trading on the floor of the New York Stock Exchange (NYSE) in New York City, U.S., December 20, 2018. REUTERS/Brendan McDermid 

A screen displays the Dow Jones Industrial Average after the close of trading on the floor of the New York Stock Exchange (NYSE) in New York City, U.S., December 19, 2018. REUTERS/Brendan McDermid 

A screen displays the Dow Jones Industrial Average after the close of trading on the floor of the New York Stock Exchange (NYSE) in New York City, U.S., December 19, 2018. REUTERS/Brendan McDermid 

A screen displays the Dow Jones Industrial Average following the close of trading on the floor of the New York Stock Exchange (NYSE) in New York, U.S., December 7, 2018. REUTERS/Brendan McDermid 

A man walks past an electronic board showing Japan's Nikkei average and Dow Jones Industrial Average outside a brokerage in Tokyo, Japan, December 5, 2018. REUTERS/Issei Kato 

A screen displays the Dow Jones Industrial Average after the close of trading on the floor of the New York Stock Exchange (NYSE) in New York City, U.S., November 28, 2018. REUTERS/Brendan McDermid 

A screen displays the Dow Jones Industrial Average after the close of trading on the floor of the New York Stock Exchange (NYSE) in New York City, U.S., November 28, 2018. REUTERS/Brendan McDermid 

A screen displays the Dow Jones Industrial Average after the close of trading on the floor of the New York Stock Exchange (NYSE) in New York City, U.S., November 28, 2018. REUTERS/Brendan McDermid 

A graph indicating the Dow Jones Industrial Average is shown on a monitor at the close of trading on the floor at the New York Stock Exchange (NYSE) in New York City, U.S., November 12, 2018. REUTERS/Brendan McDermid 

The Dow Jones Industrial Average is shown on a monitor at the close of trading on the floor at the New York Stock Exchange (NYSE) in New York City, U.S., November 12, 2018. REUTERS/Brendan McDermid 

The Dow Jones Industrial Average is shown on a monitor at the close of trading on the floor at the New York Stock Exchange (NYSE) in New York City, U.S., November 12, 2018. REUTERS/Brendan McDermid 

A screen displays a chart of the Dow Jones Industrial Average on the floor of the New York Stock Exchange (NYSE) in New York, U.S., October 24, 2018. REUTERS/Brendan McDermid 

A screen displays the Dow Jones Industrial Average after the close of trading on the floor of the New York Stock Exchange (NYSE) in New York, U.S., October 24, 2018. REUTERS/Brendan McDermid 

A screen displays the Dow Jones Industrial Average after the close of trading on the floor of the New York Stock Exchange (NYSE) in New York, U.S., October 24, 2018. REUTERS/Brendan McDermid 

A screen displays the Dow Jones Industrial Average after the close of trading on the floor of the New York Stock Exchange (NYSE) in New York, U.S., October 24, 2018. REUTERS/Brendan McDermid 

A screen displays a chart that tracks the Dow Jones Industrial average on the floor of the New York Stock Exchange (NYSE) in New York, U.S., October 17, 2018. REUTERS/Brendan McDermid 

A man looks at electronic boards showing Japan's Nikkei average (L) and Dow Jones Industrial Average outside a brokerage in Tokyo, Japan, October 12, 2018. REUTERS/Toru Hanai TPX IMAGES OF THE DAY 

A man looks at electronic boards showing Japan's Nikkei average (L) and Dow Jones Industrial Average outside a brokerage in Tokyo, Japan, October 12, 2018. REUTERS/Toru Hanai 

A man walks past electronic boards showing Dow Jones Industrial Average and and NASDAQ average (top R) outside a brokerage in Tokyo, Japan, October 12, 2018. REUTERS/Toru Hanai 

Final numbers for the Dow Jones industrial average are displayed after the close of trading on the floor of the New York Stock Exchange (NYSE) in Manhattan in New York, U.S., October 11, 2018. REUTERS/Brendan McDermid? 

Final numbers for the Dow Jones industrial average are displayed after the close of trading on the floor of the New York Stock Exchange (NYSE) in Manhattan in New York, U.S., October 11, 2018. REUTERS/Brendan McDermid 

Final numbers for the Dow Jones industrial average are displayed after the close of trading on the floor of the New York Stock Exchange (NYSE) in Manhattan in New York, U.S., October 11, 2018. REUTERS/Brendan McDermid? 

Final numbers for the Dow Jones industrial average are displayed after the close of trading on the floor of the New York Stock Exchange (NYSE) in Manhattan in New York, U.S., October 11, 2018. REUTERS/Brendan McDermid 

Final numbers for the Dow Jones industrial average are displayed after the close of trading on the floor of the New York Stock Exchange (NYSE) in Manhattan in New York, U.S., October 11, 2018. REUTERS/Brendan McDermid 

A passerby walks past an electronic boards Japan's Nikkei average, the Dow Jones Industrial Average and foreign exchange rates outside a brokerage in Tokyo, Japan, October 11, 2018. REUTERS/Issei Kato