Amazon Web Services, long the cloud-computing market leader, edged past Wall Street estimates for June-quarter revenue on Thursday with a 17.5 per cent increase, but it widely lagged the 39 per cent growth seen at Microsoft Azure and Google Cloud’s 32 per cent gain.

Amazon.com (AMZN-Q) shares dropped nearly 8 per cent before the bell on Friday, after growth in its cloud computing unit failed to impress investors, in contrast to the robust gains reported by AI-focused rivals Alphabet (GOOGL-Q) and Microsoft (MSFT-Q).

The e-commerce giant’s quarterly sales results beat expectations, but shares dropped 7% because its cloud computing arm’s growth wasn’t as strong as rivals’.