Public cloud services are the biggest disruption in the tech market in the past 15 years — and adoption is accelerating. We project that revenue from public cloud platforms, business services, and applications (software-as-a-service [SaaS]) will grow at an overall CAGR of 22% between 2015 and 2020, reaching $236 billion, which is 23% higher than our previous forecast. Further, we now forecast greater adoption of cloud services to replace conventional apps, platforms, and business services. CIOs: Use this forecast to benchmark the pace and shape of your public cloud strategies.