McKinsey's Study on Unlocking the Potential of the Internet of Things
McKinsey's bottom-up analysis for the applications they size estimates that the IoT has a total potential economic impact of $3.9 trillion to $11.1 trillion a year by 2025. At the top end, that level of value—including the consumer surplus—would be equivalent to about 11 percent of the world economy. See the details of the study here.