Starbucks shares fell sharply on Tuesday after the company’s preliminary fourth-quarter results revealed a decline in sales in its two largest markets— the US and China— raising concerns about the coffee giant’s growth prospects.

Sales in the US, Starbucks’ core market, showed signs of slowing, with fewer customer visits as inflation pressures weighed on consumer spending. In China, where the company has been aggressively expanding, sales dropped further than expected due to continued economic challenges and lingering effects of COVID-19 restrictions.

Investors reacted swiftly, with Starbucks’ stock tumbling more than 4% in after-hours trading. The company had previously raised its forecast for 2024, banking on a strong recovery in international markets, particularly in China. However, these latest results cast doubt on those expectations, with both regions underperforming.

The weaker-than-expected performance in China is especially troubling for Starbucks, as it has poured significant resources into expanding its footprint in the country. China is viewed as a long-term growth engine for the company, but the recent economic slowdown and consumer uncertainty are presenting significant hurdles.

In the US, higher operating costs and softer demand have also chipped away at profitability, with the company grappling to find the right balance between pricing strategies and maintaining customer loyalty.

Analysts are beginning to temper their outlook on Starbucks, citing these headwinds as potential drags on future growth. While the company remains optimistic about its long-term trajectory, the current challenges in its key markets signal a need for strategic adjustments moving forward.

For now, Starbucks’ stock remains under pressure, with investors closely watching for more detailed guidance in the company’s upcoming earnings call. As the broader macroeconomic environment remains uncertain, Starbucks’ ability to navigate these challenges will be critical to regaining investor confidence.