Fast-growing nontraditional grocery-retailing formats such as limited-assortment banners and natural and organic specialists, combined with a handful of high-performing traditional supermarket banners, have helped slow the industry’s market-share losses to the warehouse and supercenter formats in recent years, according to an analysis of government sales data by Northbrook, Ill.-based DSR Marketing Systems. The total grocery market grew 14% to $645 billion between 2007 and 2011. And while supermarkets lost share as a group during that time, the rate of decline slowed as the “growth formats” and some traditional chains like Publix Super Markets and Kroger made up for the declines of others.