Microsoft’s shares have hit an all-time high after the company posted better-than-expected quarterly profits.

Its focus on cloud computing helped the software giant to post a $4.7 billion profit for Q3 of 2016.

Microsoft CEO Satya Nadella has focused on building the company’s expertise in cloud-based services amid slowing PC sales.

Shares rose 6% to $60.73 in after-hours trading.

The previous high was $59.97 in December 1999, close to the peak of the dot-com boom, shortly before Steve Ballmer replaced Bill Gates as CEO.

When Satya Nadella succeeded Steve Ballmer in 2014, Microsoft’s shares were trading below $37.

Investor confidence in Microsoft has been restored by focusing on mobile and cloud computing rather than its traditional products such as the Windows operating system and Office software.

Individuals and businesses are increasingly accessing computing services such as servers, databases, software and storage that are provided over the internet (“the cloud”).

Satya Nadella said the changing business environment meant this was paying off.

“It’s not just the Silicon Valley startups anymore; it is the core enterprise that is also becoming a digital company. And we are well-positioned to serve them,” he said.

Revenue from Microsoft’s Office 365 cloud service increased 8% in the quarter while revenue from its Surface tablet – pitched as a rival to the iPad – rose 38%.

While revenue from its flagship Xbox – Microsoft’s games console – fell, the number of people playing online rose to 47 million from 39 million a year.