In honor of NC-17 rated "Blue Is The Warmest Color" -- which is continuing to find strong numbers as it expands across the U.S. ($379,278 and counting) --  Indiewire is taking a look back at the history of the controversial rating, which has been in effect for over 23 years now.

The rating was inaugurated by the Motion Picture Association of America (MPAA) in September 1990 with the release of Philip Kaufman's "Henry & June" (which, to this day, is the second highest grossing film released with the rating). Initially standing for "No Children Under 17 Admitted," the MPAA changed its meaning to "No One 17 and Under Admitted" in the late 1990s despite the acronym now no longer making sense.

READ MORE: IFC Center Will Admit High Schoolers to NC-17 Rated 'Blue is the Warmest Color'

Thirty films have been released with an NC-17 since, the vast majority of them receiving the rating due to sexual content. Of them, only 14 have grossed over $1 million, and only two - "Henry & June" and "Showgirls," the latter of which is far and away the highest grossing NC-17 film - taking in over $10 million.

Beyond, most obviously, "Showgirls," most of the films rated NC-17 are actually exceptional examples of challenging independent and world cinema. From Pedro Almodovar's "Bad Education" and "Tie Me Up! Tie Me Down!" to Ang Lee's "Lust, Caution," Todd Haynes' "Poison," Steve McQueen's "Shame" and David Cronenberg's "Crash," "Blue is the Warmest Color" should proudly stand alongside its NC-17 predecessors. And hopefully, it manages to continue to find some respectable box office in the process, helping relieve distributors' fears of releasing films with the rating (which, as many of us learned through "Blue," is merely a "recommendation").

In the meantime, take a look at the 20 top grossing NC-17 films of all-time (a list "Blue" should easily be on by next weekend):

Michael Fassbender in "Shame"
Michael Fassbender in "Shame"

1. Showgirls (MGM, 1995) - $20,350,754
2. Henry & June (Universal, 1990) - $11,567,449
3. The Cook, The Thief, His Wife and Her Lover (Miramax, 1990) - $7,724,701
4. Bad Education (Sony Pictures Classics, 2004) - $5,211,842
5. Lust, Caution (Focus, 2007) - $4,604,982   
6. Tie Me Up! Tie Me Down! (Miramax, 1990) -   $4,087,361  
7. Shame (Fox Searchlight, 2011) -  $3,909,002
8. The Dreamers  (Fox Searchlight, 2004) -   $2,532,228    2004
9.  Crash  (Fine Line, 1996) -  $2,038,450 
10. Bad Lieutenant  (Aries, 1992) -    $2,000,022  
11. Killer Joe  (LD, 2012) -   $1,987,762 
12. Wide Sargasso Sea (New Line, 1993) -  $1,614,784 
13. A Dirty Shame (Fine Line, 2004) -   $1,339,668   
14. Whore  (Trimark, 1991) -  $1,008,404 
15. Poison   (Zeitgeist, 1991) -   $787,280    1991
16. Young Adam  (Sony Pictures Classics, 2004) -  $767,373
17. Mysterious Skin  (Tartan, 2005)  -  $713,240  
18. Inside Deep Throat  (Universal, 2005) -  $691,880  
19. Dice Rules  (7Art, 1991)  -  $637,327   
20. Orgazmo  (October, 1998)   $602,302