According to the study made by J.D. Power and Associates, the 2009 Wireless Customer Care Performance has ranked Verizon Wireless as the top among the U.S. carriers. On the basis of 9,600 customers, the survey discovers that customers with extended warranties and unlimited calling plans were the ones who are happier with their wireless carrier than those with base plans. Verizon Wireless notched a score of 753, and was tailed narrowly by T-Mobile which had a score of 752. AT&T was ranked about average and was followed by Sprint.