Microsoft (MSFT 0.33%) shares fell in after-hours trading on Tuesday following the release of the company's fiscal-fourth-quarter earnings report. Microsoft's quarterly earnings and revenue exceeded analysts' expectations, but not to a significant extent. Microsoft earned an adjusted $0.62 per share, better than the consensus estimate of $0.56, on revenue of $22.2 billion (analysts had been looking for $22 billion).

Microsoft Windows Logo

Windows continues to decline
Microsoft's Windows business continued its steady decline in the fourth quarter. Windows Pro revenue fell 21% as the temporary bump caused by the end of Windows XP support came to an end. Non-Pro revenue declined even more starkly -- 27%. Microsoft blamed the decline on the upcoming launch of Windows 10, as its hardware partners managed their inventory more aggressively. In total, Windows OEM revenue was down 22% on an annual basis.

Windows Phone revenue fell by a stunning 68%, though the decline was not as significant as it initially appears. In the same quarter last year, Microsoft recognized $382 million from the end of its Windows Phone agreement with Nokia.  Microsoft actually sold 10% more Lumia smartphones (8.4 million) in the fourth quarter than in the prior year. 

Commercial cloud growth is slowing down
But Microsoft's future is likely to be determined more by its cloud businesses than its operating system. Microsoft's cloud continues to grow rapidly, but that growth is starting to slow down.

Microsoft's Commercial Cloud is primarily composed of three products: Office 365, Dynamics CRM, and Microsoft Azure. Revenue rose 88% on an annual basis, and is now on pace for an annualized run rate of more than $8 billion. Yet last quarter Microsoft's Commercial Cloud revenue grew 106%, and in the two quarters before that 114% and 128%, respectively. Some of Microsoft's biggest bulls, including the hedge fund ValueAct, have argued for the company on the basis of these cloud businesses. While they continue to grow, the slowing growth rate may have contributed to Microsoft's sell-off.

Surface, Xbox, Office and Bing
Results from Microsoft's other segments were mixed. Surface, Xbox, and Bing showed some positive momentum, but Office revenue fell.

Microsoft's Surface-related revenue rose $888 million in the fourth quarter, up 117% from the prior year. Microsoft cited continued demand for the Surface Pro 3, the introduction of the Surface 3, and accessory sales to explain this gain. In total, Microsoft's Surface business generated $3.6 billion in fiscal year 2015, up 65% from 2014. That's impressive growth, but for comparison, Apple's Mac and iPad businesses each generated more than $5 billion last quarter.

Microsoft's other big hardware platform, the Xbox, enjoyed more modest growth. During the quarter, Microsoft sold 1.4 million Xbox consoles -- a gain of 30% year-over-year. However, revenue rose only 10% as Microsoft has been steadily trimming the price of its consoles to spur sales. Notably, Microsoft did not specify how many Xbox Ones it had sold and how many of the older Xbox 360s. The Xbox One will receive a version of the Windows 10 operating system later this year, and it could serve as a key catalyst for attracting developers to the platform.

Microsoft's search engine, Bing, remains in a distant second place in the U.S., but it did experience a slight gain in market share. Microsoft now has 20.3% of the U.S. search market, and search advertising revenue rose 21% during the quarter.

Microsoft's Office-related revenue tumbled during the quarter. Consumer revenue fell 42% on an annual basis, while commercial Office revenue fell 18%. Among business users and consumers, Microsoft cited the ongoing shift to Office 365, but also drew particular attention to the Japanese PC market. Of the 42% decline in consumer Office revenue, Microsoft attributed 19% to weak Japanese PC sales. Microsoft now has 15.2 million consumers subscribing to Office 365.

Microsoft remains a volatile stock as it continues to transition its business to one that's centered on cloud services and mobile software. Long-time investors in the Windows-maker should be accustomed to these moves, as Microsoft shares have experienced fairly wild swings in the wake of prior earnings reports.