Fill in the Blanks BEL11 p12Online version ............ by Tea Cher 1 spam marketing recipients industries video campaigns revenue mobile inbox newsletters digital average techniques Marketers who add to their email see an rise in of 40 percent . Twenty - seven percent of U . S . mobile users believe e - mail messages are difficult to read because of incorrect layouts . Only 12 percent of use responsive design to optimize their layouts for mobile devices . Twenty - nine percent of the e - mail messages that reach a user ? s are newsletters . Thirty - seven percent of marketers integrate e - mail with mobile tactics . Education , retail , and computer hardware / electronics are the best performing in e - mail marketing . Twenty - one percent of email report e - mail as , even if they know it isn ? t .