Key Takeaways T fell 5.1% in three months, lagging the S&P 500 and peers like Verizon and Comcast. AT&T is affected by rising customer retention costs amid intensifying competition in the wireless market.T is expanding 5G, edge computing and satellite links, adding EchoStar spectrum and working with ASTS.AT&T, Inc. (T) has declined 5.1% over the past three months compared to the Wireless National industry’s decrease of 7%. The stock has underperformed compared to the Zacks Computer & Technology sector and t ...