In 2006 alone, retailers lost almost $2 billion because of consumer security fears, with about one-half of those losses ($913 million) coming from people who avoided sites that seemed to be less secure and the rest (about $1 billion) came from consumers who were too afraid to conduct e-commerce business at all, according to a Gartner survey of 5,000 U.S. adults in August that the research firm published on Nov. 27.