NEW YORK—Sales for the 10 largest retailers on the VM Top 50 list for 2012 increased by 3.8 percent from an estimated $6,533.7 million in 2011 to an estimated $6,785.1 million in 2012, while their share of total sales for the Top 50 dipped from 85.9 percent in 2011 to 84.1 percent in 2012. The mass merchants’ share of Top 50’s estimated optical U.S. sales remained the same at 31.6 percent, with their total estimated 2012 sales increasing 4.6 percent from $2,439.2 million in 2011 to $2,551.4 million in 2012.