Hit Parade is back for non-Slate Plus listeners! Upcoming episodes will be split into two parts, released two weeks apart. For the full episode right now, sign up for Slate Plus and you'll also get The Bridge, our Trivia show and bonus deep dive into our subjects. slate.com/hitparadeplus.In Part 2 of this episode of Hit Parade, we continue the story of how Nirvana’s Nevermind ousted Michael Jackson’s Dangerous from the top of the Billboard album chart, Chris Molanphy examines the chart dynamics that not only ushered in the grunge era but also invented a new music sales strategy, the post-Christmas album, and how that trend has been shaped and changed by the rise of rap, and the surprise album drop.Podcast production by Benjamin Frisch.Learn more about your ad choices. Visit megaphone.fm/adchoices