With the fourth-quarter 2012 reporting season wrapping up, it is time to parse the information and examine which carriers stumbled and which ones grew their businesses during the three-month period. Research firm Strategy Analytics has supplied a number of charts displaying key performance indicators (KPIs) for the top U.S. wireless operators from 2012's final quarter. Major metrics provided for each carrier include subscriber figures (retail and wholesale), churn, ARPU and revenue. Special Report