NEW YORK, NEW YORK - SEPTEMBER 21: U.S. President Barack Obama exits the stage after speaking at the U.S.-Africa Business Forum at the Plaza Hotel, September 21, 2016 in New York City. The forum is focused on trade and investment opportunities on the African continent for African heads of government and American business leaders. (Photo by Drew Angerer/Getty Images)

NEW YORK, NEW YORK - SEPTEMBER 21: U.S. President Barack Obama speaks at the U.S.-Africa Business Forum at the Plaza Hotel, September 21, 2016 in New York City. The forum is focused on trade and investment opportunities on the African continent for African heads of government and American business leaders. (Photo by Drew Angerer/Getty Images)

NEW YORK, NEW YORK - SEPTEMBER 21: President of Nigeria Muhammadu Buhari arrives to speak at the U.S.-Africa Business Forum at the Plaza Hotel, September 21, 2016 in New York City. The forum is focused on trade and investment opportunities on the African continent for African heads of government and American business leaders. (Photo by Drew Angerer/Getty Images)

NEW YORK, NEW YORK - SEPTEMBER 21: Former New York City mayor Michael Bloomberg speaks at the U.S.-Africa Business Forum at the Plaza Hotel, September 21, 2016 in New York City. The forum is focused on trade and investment opportunities on the African continent for African heads of government and American business leaders. (Photo by Drew Angerer/Getty Images)

NEW YORK, NEW YORK - SEPTEMBER 21: President of Nigeria Muhammadu Buhari speaks at the U.S.-Africa Business Forum at the Plaza Hotel, September 21, 2016 in New York City. The forum is focused on trade and investment opportunities on the African continent for African heads of government and American business leaders. (Photo by Drew Angerer/Getty Images)

NEW YORK, NEW YORK - SEPTEMBER 21: U.S. President Barack Obama speaks at the U.S.-Africa Business Forum at the Plaza Hotel, September 21, 2016 in New York City. The forum is focused on trade and investment opportunities on the African continent for African heads of government and American business leaders. (Photo by Drew Angerer/Getty Images)

NEW YORK, NEW YORK - SEPTEMBER 21: National Basketball Association (NBA) commissioner Adam Silver listens as U.S. President Barack Obama speaks at the U.S.-Africa Business Forum at the Plaza Hotel, September 21, 2016 in New York City. The forum is focused on trade and investment opportunities on the African continent for African heads of government and American business leaders. (Photo by Drew Angerer/Getty Images)

NEW YORK, NEW YORK - SEPTEMBER 21: U.S. President Barack Obama speaks at the U.S.-Africa Business Forum at the Plaza Hotel, September 21, 2016 in New York City. The forum is focused on trade and investment opportunities on the African continent for African heads of government and American business leaders. (Photo by Drew Angerer/Getty Images)