Datadog Inc (NASDAQ:DDOG) shares tumbled more than 18% on Thursday even after the software company delivered what analysts called a high-quality quarter, as investors focused on decelerating bookings growth and softer-than-expected third-quarter guidance. Datadog's revenue grew 35.6% year-over-year in the second quarter, ahead of the company's 29-31% guidance range and accelerating from 32% growth in the first quarter.