Key Takeaways AT&T posted a mixed first-quarter earnings report Wednesday, missing revenue estimates but reporting additions to its mobile and internet subscriber base. The telecommunications giant said lower sales volumes and a nearly 8% year-over-year drop in its Business Wireline segment hurt its total revenue. AT&T affirmed its full-year guidance, projecting wireless service and broadband revenue to grow 3% and 7%, respectively. AT&T (T) shares jumped in premarket trading Wednesday following the release ...