Historic: Miley Cyrus song fails to chart Downhill for Miley?

For the first time in her career, Miley Cyrus failed to break the charts. We Belong to the Music, with Timbaland, is one of her best songs in my opinion. I call it Party in the U.S.A. Part II. Yet it has failed to break any Billboard charts after five weeks of release. Is Miley Cyrus as relevant as Hilary Duff?