RNG earnings call for the period ending December 31, 2018.: Greetings, and welcome to RingCentral Fourth Quarter 2018 Earnings Conference Call. At this time, all participants are in a listen-only mode. A question-and-answer session will follow the formal presentation. (Operator Instructions) As a reminder, this conference is being recorded. Thank you. Good afternoon, and welcome to RingCentral's fourth quarter 2018 earnings conference call. I'm Ryan Goodman, RingCentral's Director of Investor Relations. Joining me today are; Vlad Shmunis, Founder, Chairman and CEO; David Sipes, Chief Operating Officer; and Mitesh Dhruv, Chief Financial Officer.