Marketers are migrating to digital channels en masse. According to a recent eMarketer study, U.S. e-commerce sales will total $259 billion in 2013—a 14.8% annual increase over 2012's $225.5 billion. But there's a missing link. When consumers research products online, the majority of purchases take place offline, either over a phone or in a store. Forrester Research, Yahoo, and comScore all reach the same conclusion—as much as 92% of purchases take place offline following online consumer activity, while most digital marketers target online conversions only. Targeting isn't about clicks, it's all about sales, and 92% is a large percentage of missing data.