Well, no, not yet. Microsoft doesn't break out Azure separately. It's usually included in their "Intelligent Cloud", which is the largest segment, but that also includes SQL Server (a big money maker), Windows Server, GitHub, and other stuff. "Commercial Cloud" revenue (which is all the cloud portions of their products, from Azure to Office 365 Commercial) was $51.7Bln of $143Bln overall. So yes, Azure makes a lot of money, but not "most".