Apple's iPhone sales in China plunged in the last week of December, with Jefferies analysts anticipating the sales slump could lead to a double-digit decline for 2024.

In the last week of December, iPhone sales in China were down 30% from the same period a year earlier, according to estimates by Jefferies analysts. By contrast, Android and Huawei sales stayed relatively flat.

Jefferies noted the double-digit decline came as Apple faces "a very high base," as well as competition in the region from Chinese phone makers including Huawei. Apple lost approximately 0.4 percentage points in market share exiting 2023, while Huawei, Xiaomi, and others gained market share.

In its fiscal fourth quarter, Apple had reported revenue dropped 0.7% from the year before to $89.5 billion, with sales in China down 2.5% to $15.1 billion. China accounted for about 17% of the company’s overall revenue.

While some analysts suggested worries about Apple's sales slump in China could be overblown, others have noted that competiti൩on from other s🍎martphone brands could pose a real threat to the iPhone maker in the region.

Jefferies analysts said they anticipate iPhone volume in China could continue to decline in the new year with another double-digit drop, contributing to an "even higher revenue pressure in China in 2024."

Apple shares were down 0.6% at $184.46 per share at about 11:50 a.m. ET Tuesday. They've gained over 41% over the past year.