Grading the top 8 U.S. carriers in the second quarter

As the second-quarter reporting season comes to a close, it's time to start parsing the information to see which carriers slipped and which ones managed to get ahead. Research firm Strategy Analytics breaks down the metrics, from churn, ARPU and revenue to quarterly net adds. How did Verizon's net adds compare to AT&T's? How much progress is Sprint making in its turnaround? To see how the operators stack up against one another, check out this special report.