Public Cloud services — Software-as-a-Service (SaaS), Infrastructure-as-a-Service (IaaS) and Platform-as-a-Service (PaaS) — will grow at a combined rate of 20% annually for the next decade, reaching $428 billion in 2026. That is the conclusion – based in part on recent earnings results from Amazon, Microsoft and IBM – of Wikibon’s just-published Public Cloud Market Forecast 2015-2026.

Authored by Wikibon analysts Dr. Ralph Finos, David Floyer, Brian Gracely and Stuart Miniman, the report examines the positioning, strengths and weaknesses and growth drivers of public cloud by its three main segments. It finds that SaaS will remain the largest part of public cloud by revenue, although its share will shrink from 67 percent of the market to 60 percent of the much larger market in 2026.

The report also looks at the market by user categories, including application users, IT departments and application developers. Under PaaS it further segments the market into PaaS from IaaS providers like Amazon Elastic Beanstalk, PaaS from SaaS providers like Salesforce.com’s Sales Force 1, and PaaS from development environment providers like IBM Bluemix, examining the strengths and weaknesses of each.

This report only mentions private cloud and hybrid cloud in passing, but it acknowledges the importance of these owned platforms, noting that hybrid cloud “is likely to become the cloud approach of choice as enterprises will be able to deploy workloads to the optimal cloud platform based on requirements.” Wikibon intends to produce reports on both these major segments of the overall business cloud market later this year. It also does not break the market down by vendor or discuss the strengths and weaknesses of individual vendors.

The report provides an extensive list of definitions starting with public cloud itself and its main divisions and including definitions of numerous terms, all derived from the National Institute of Standards and Technology (NIST).

The Wikibon analysts conclude with the thought that while public cloud will grow rapidly over the decade, it is unwise to try to pick winners at this point. Therefore, it recommends that users develop an adaptive strategy that exploits the best of multiple offerings while avoiding becoming locked in to any one or two providers.

A summary of the report is here. Access to the full report requires a Wikibon Premium subscription.

In the CUBEconversation below John Furrier of SiliconANGLE along with Dave Vellante, Stu Miniman and Brian Gracely of Wikibon dig deep into the current state of public cloud (44:20).

Photo via Adina Voicu