65% of newsletters are used for personal, 40% for business reasons

Jacob Nielsen studied 101 of the 345 newsletters that participants were already subscribed to on their own initiative, testing users' newsletter experiences over a four-week period in most cases, and a two-week period in a few cases. This longitudinal approach allowed more emphasis on how people deal with incoming newsletters during their workday. It also let us test many more B2B and intranet newsletters than we could cover in the first study, which mainly tested B2C newsletters. Of the newsletters received by users in our second study, 65% were for personal purposes and 40% were for business purposes (users viewed 5% of newsletters as both personal and business, so they counted them twice).