New York: Microsoft Corp.’s Windows 10 has reached more than 75 million devices in almost a month since the operating system was released, according to Yusuf Mehdi, the company’s marketing chief for Windows and devices.

More than 90,000 personal-computer and tablet models have upgraded to the new OS, which is running in 192 countries, Mehdi said Wednesday in a series of tweets. The app store for Windows 10 has had six times more downloads per device than Windows 8, he wrote.

The Redmond, Washington-based company has promised shareholders that Windows 10 would reach 1 billion users within three years, which would be its fastest adoption rate ever. Within the first 24 hours of the 29 July release, 14 million devices were running the operating system, Mehdi wrote in a blog post last month. Chief executive officer Satya Nadella has said the revenue bump from the new OS will come mostly two quarters from now.

“Adoption for Windows 10 is professing ahead of Street expectations," Daniel Ives, an analyst at FBR Capital Markets, said in an e-mail. “Nadella finally got it right this time, as consumers and enterprises like what they see with this new flagship platform."

Ives had projected that 50 million devices would be running on Windows 10 by the end of August. Windows 8 reached fewer than 15 million devices in its first month, he said. It took more than half a year for Microsoft to sell 100 million licenses for Windows 8 after its release. Ives rates the stock outperform.

Microsoft shares gained 5.5 percent to $42.71 at the close in New York. The Standard & Poor’s 500 Information Technology Sector Index advanced 5.3 percent as stocks rallied to end a six-day plunge.

Mehdi also tweeted that Cortana, Microsoft’s voice- controlled personal assistant, has told more than 500,000 jokes since the release. Nadella has said that Cortana is “perhaps the biggest innovation in productivity we’ve done." Bloomberg