https://www.theverge.com/2019/1/29/18202734/apple-earnings-q1-china-fall-drop-us-growth

Apple pinned the blame for its falling sales revenue primarily on issues in China, and now its quarterly earnings release shows just how much its sales in the region fell short. During its 2018 holiday quarter, Apple brought in $13.2 billion in Greater China, down from nearly $18 billion during the same period the prior year.

That nearly $5 billion dip was more than enough to wipe out small gains in the Americas and the rest of Asia Pacific. Sales revenue also fell slightly in Europe and Japan, which, combined, accounted for a $1 billion annual decline.