With Amazon disclosing publicly for the first time its public cloud revenues as part of its latest quarterly revenues, many are wondering how Microsoft stacks up with Azure.

Making an oranges-to-oranges comparison between the the largest public cloud vendor, Amazon, and Microsoft -- believed by many to be No. 2 -- isn't straightforward.

Microsoft does not break out its public-cloud, or even its combined public/private-cloud revenues. Instead, it now reports them as part of what it calls "Commercial Cloud." Commercial Cloud also includes revenues from Azure, Office 365 and Dynamics CRM Online.

Back in 2013, Microsoft officials told Bloomberg that Azure (formerly known as Windows Azure) sales had topped $1 billion. The fine print revealed that $1 billion figure included not just Azure, but also "software provided to partner companies that create related cloud services that run on Windows and the SQL Server database."

But software -- Windows Server, Azure Pack, SQL Server and other pieces that Microsoft provides to its cloud hosting partners is not part of "Commercial Cloud" under Microsoft's current reporting structure. Microsoft infrastructure software that customers use in their own datacenters to create hybrid or private clouds -- again, products like Windows Server, SQL Server, SharePoint Server, Exchange Server, etc. -- also is not counted in Microsoft's cloud revenues. And any of Microsoft's own consumer services that run on Azure, in whole or in part, such as Outlook.com, Xbox Live, OneDrive, and the like, also aren't part of "Commercial Cloud" in Microsoft's accounting.

Last quarter (Q2 FY'15), Microsoft CEO Satya Nadella said Microsoft's Commercial Cloud was at a run rate of $5.5 billion, which represented "triple digit growth."

It's worth noting that run rate is not exactly the same as revenues. One billion in revenues means the actual revenues are $1 billion. But run rate is about future performance, based on current results. It's an extrapolation.

Microsoft's run rate for Commercial Cloud for this quarter is $6.3 billion. The company isn't disclosing how much of this is Azure vs. Office 365 and CRM Online. Microsoft also isn't disclosing revenues for Azure, nor is it disclosing revenues or number of subscribers for Office 365 business plans or CRM Online. (Microsoft is saying it has 12.4 million Office 365 consumer subscribers now --up from 9.2 million last quarter -- but the company won't share that number for Office 365 Business, Government and/or Academic subscribers.)

If you wanted to try to pin a number of Commercial Cloud for this quarter, I guess you could divide 6.3 by 4 and get $1.6 billion. But that figure encompasses more than just Azure.

AWS had revenue of $1.57 billion for its first quarter and operating income of $265 million for AWS, according to its earnings report today. If that pattern continues, AWS could bring in $6.26 billion in revenues for Amazon in 2015.

There are some "sources said" reports out there about how much Microsoft is making from Azure alone. There are reports Microsoft is squeezing its salesforce to try to get customers to move from trials and credits to paying subscriptions.

But Microsoft execs won't budge in terms of disclosing on the record how much it's making right now from the public cloud. And that's the real number needed to do a true comparison with Amazon....