This week's Billboard 200 featured the soundtrack to Furious 7 reaching no. 1 after four weeks on the charts. What's propelled the album to higher and higher sales every week? For one thing, the release of the film. More importantly however is the new metrics behind the Billboard 200, which now counts song streams and downloads toward "equivalent album sales." When an album has one song that really hits home with the population, that in turn helps the album that features it to move higher on the Billboard 200 charts. For Furious 7, that song is "See You Again," a track by Wiz Khalifa paying homage to deceased actor Paul Walker. The single dominated digital downloads last week, racking up 464,000 units sold, which equates to 46,400 "album sales" by itself.

Let's take a look at the last five soundtracks to hit no. 1 on the Billboard 200 and rank them based on how much they depended on a hot single to drive sales.

Note: As the new Billboard metrics didn't set in until late last year, the actual sale of singles from these albums can't directly be attributed to the Billboard 200 success of the albums. However, it can be argued that one smash hit will drive listeners to buy the whole album.

05) Frozen and "Let It Go" by Idina Menzel

Although Furious 7 is already the second soundtrack to top the Billboard 200 during 2015, nothing coming out anytime soon is going to challenge Frozen for soundtrack sales in the near future. Heck, it was so successful that Disney released a special DVD designed for karaoke purposes. The obvious standout, based on viral videos and a multitude of covers, was "Let It Go." For some odd reason, Disney opted to release a version of the song sung by Demi Lovato as the first single from the album—although it was a moderate success, peaking at no. 38 on the Hot 100, doesn't it make more sense to just release the official version when you've got Idina Menzel singing it? Nobody complained about "Defying Gravity"...we're just saying. Menzel's version peaked at no. 5 on the Hot 100 and was the true driving force behind the "Let It Go." It wasn't the only hit off of the album however, as "Do You Want To Build A Snowman?" went to no. 51. That leads to one of two conclusions: Either "Let It Go" drove millions of buyers to pick up the album, or the quality of the record as a whole drove buyers to pick it up in droves.

04) The Hunger Games and "Safe & Sound" by Taylor Swift and The Civil Wars

The Hunger Games film franchise learned a thing or two from the Twilight film series and grabbed some of the hottest musicians to turn out a few tracks for the official soundtrack. Taylor Swift was about as big as it got during 2012 when the first film was released, and her original single "Safe & Sound" (with The Civil Wars) was received accordingly by Top 40 listeners, taking it up to no. 30 on the Hot 100. That may not seem like much compared to star Jennifer Lawrence's recording of "The Hanging Tree" for last year's Mockingjay film, but it trumped Lorde's "Yellow Flicker Beat" from the same flick by four Hot 100 places. That also makes it the highest-charting single from any of the soundtracks on this list, aside from Menzel's "Let It Go."

03) Les Misérables and "I Dreamed A Dream" by Anne Hathaway

Disney was, theoretically, taking a huge risk with its film version of the musical Les Misérables. Although the play had done quite well on Broadway, that doesn't mean a movie theater version was going to drum up the same support, much less enough revenue to pay off the all-star cast that featured, among others, Hugh Jackman, Russell Crowe and Anne Hathaway. The best thing they could do is build the hype by releasing a single, and they unsurprisingly opted for "I Dreamed A Dream," the most popular tune from the musical. The song is sung by Fantine, Hathaway's character. It actually generated a modest amount of success, cracking the Hot 100 and peaking at no. 69. Still, that's not the sort of attention that's going to flood the box office. One item working against Hathaway and Disney was that Susan Boyle's now famous version of the song from The X Factor had taken the world by viral storm during 2009 (even if that only led to no. 62 on the Hot 100). Listeners may have been burnt out on the song, or wise enough to know that Hathaway, no disrespect intended, wasn't going to beat it. Still, the film itself was a box office smash nonetheless.

02) Empire singles released?

Empire turned a lot of heads this year, both on television and in the music industry. The hit program saw its audience rise consistently from week to week until the middle of the season, where it maintained one of the highest weekly viewerships during weeknights. WhenEmpire: Original Soundtrack from Season 1 debuted five weeks ago, it caught many by surprise by beating out Madonna's new album Rebel Heart on the Billboard 200. Rebel Heart actually sold more full albums, so surely that indicated listeners and fans had latched onto one or several singles, thus propelling the soundtrack higher up on the 200, right? Somewhat surprisingly, despite begin a show focused on the hot genres of hip-hop and R&B, Empire didn't release any singles. Those extra streams and downloads were largely just people interested in listening to the album as a whole. When and if Empire drops a new soundtrack compilation, they should consider bringing in a pro and releasing a superstar single as well...more money in the bank.

01) Guardians of The Galaxy and...every song?

The storyline of the mixtape featured in Guardians of The Galaxy is that protagonist Peter Quill's mother gave it to him, featuring the music popular during her childhood (the early '70s). Therefore every track featured on the album was a hit unto itself. So why isn't the Guardians of The Galaxy Awesome Mix Vol. 1 ranked at no. 5 on this list instead of no. 1? For one thing...nothing on this soundtrack was available for single download. You either bought the entire album or nothing at all. Even if you did drop the $9.99 for the entire record online, songs downloaded as part of an album don't count toward the digital downloads charts. Theoretically, if you wanted to download The Jackson 5's "I Want You Back," you could pick it up off of a Jackson compilation but that wouldn't turn up as part of Guardians' sales total. Therefore we have to credit the soundtrack with relying the least upon it didn't even give listeners a chance to download individual songs.