Amazon’s cloud group grew recorded revenue growth of 18% in the second quarter, slightly ahead of analysts’ estimates.

Amazon Web Services continues to lead the cloud infrastructure market, but is facing intensifying pressure from Microsoft and Google, as all three companies ramp up investments in artificial intelligence to take advantage of booming demand.

Microsoft and Google reported better-than-expected cloud results for the latest quarter, with higher growth rates than Amazon.

On Wednesday, Microsoft CEO Satya Nadella said revenue from Azure and other cloud services exceeded $75 billion in the fiscal year ending June 30, with growth in the quarter of 39%. It’s the first time Microsoft has provided a dollar figure for the business. Last week, Alphabet reported revenue of $13.62 billion for its cloud computing business, a 32% increase from a year ago.

AWS’ revenue for the second quarter totaled $30.87 billion, Amazon said on Thursday. Analysts polled by StreetAccount had expected $30.8 billion. AWS now represents 18% of Amazon’s revenue.

The cloud remains a profit center for Amazon. AWS generated $10.2 billion in second-quarter operating income, trailing the average analyst estimate of $10.9 billion, according to StreetAccount. Amazon’s total operating income was $19.2 billion.

During the quarter, AWS said it would open a data center region in Chile before 2027, and PepsiCo announced a multi-year agreement that involves moving workloads to the Amazon cloud.

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