After nearly twenty years of performing, we know what to expect when Christina Aguilera opens her mouth: a wail or a run. Both have been around since her “Genie in a Bottle Days,†though the wailing has increased while the running has decreased slightly. The wail is a cross between an American Idol–style belt and the sound a cat makes when you step on her tail. It goes a little like this: “woAAAAAAAAAAA!.†The run is every time her voice bounces up and down rapidly like Aretha Franklin in an earthquake. It goes a little like this: “WOoOoOoOoOoah.†On her new record, the wailyness and runnyness are as strong as ever. Whether the song sounds like an Adele or Rihanna hand-me-down, her tricks shine through. We made a handy graph to represent the runnyness and wailyness of each song.