61% of adult Americans said they were very or extremely concerned about the privacy of personal information when buying online, an increase from 47% in 2006, University of Southern California’s Center for the Digital Future says. Concerns about credit card security have largely stabilized, with 57% very or extremely concerned in 2007. It was 53% in 2006. As of 2007, 67% of adult Internet users shop online, compared with just half a year earlier. Most spend $100 or less a month, and two-thirds of online shoppers have reduced buying at brick-and-mortar stores. Online parents are more likely than ever to withhold Internet use as punishment – 62% in 2007, compared with 47% a year earlier and 32% in 2000.