A few years ago you’d have been hard pressed to find cloud services—remote servers that allow businesses to host software and manage data—mentioned in a tech company’s annual report, now it’s a line item. In 2014 spending on public and privately hosted clouds accounted for less than 30% of IT spending. By 2019 it could account for almost half. Microsoft and Amazon are two of the biggest players. Cloud services already account for a third of Microsoft’s revenues while Amazon has doubled its cloud business in less than two years.