The rock and roll generation, who will become the parents, grandparents, and great-grandparents of the post-rock generation will consist of people born between 1940 and 1995. While rock and roll music will be replaced in popularity with world beat music and dance/electronica music either in or around the year 2015-2020, these people will collect the vinyls, 8-tracks, cassettes, and compact discs containing their "precious rock and roll music" and keep them for collection (and as rock and roll music becomes rarer, the value goes up and most are tempted by the 2030s to sell them in order to start small businesses or go on vacations of a lifetime).