Review the timeline and answer the question.
July 2018: The United States announces 25% tariffs on $24 billon of Chinese imports; China responds with similar tariffs on $34 billion of US imports.
September 2018: The United States places 10% tariffs on $200 billion of Chinese imports; China responds with similar tariffs on $60 billion of US imports.
May 2019: The United States increases tariffs on $200 billion of Chinese imports from 10% to 25%; China responds by increasing tariffs on $60 billion of US imports.
How did these developments affect trade between the countries?