Marketers are increasing their digital budgets while fewer of them grasp their return-on-investment, according to an Econsultancy survey for Responsys. More than 7 in 10 companies say they will spend more on digital, but the number of them saying they have a "good" or "very good" understanding of ROI dropped from 55% to 50%, the study showed. Agencies report that their clients' understanding of digital ROI is also eroding, with 36% ranking it "poor" or "very poor."