Question: When was a ballet company founded who's most popular performance is a two-act ballet choreographed by Marius Petipa and Lev Ivanov?

Context paragraphs:
Swan Lake (1895): The 1917 Petipa/Ivanov/Drigo revival of Swan Lake is a famous version of the ballet "Swan Lake", (ru. " Лебединое Озеро"), (fr.  "Le Lac des Cygnes").  This is a ballet by Pyotr Ilyich Tchaikovsky based on an ancient German legend, presented in either four acts, four scenes (primarily outside Russia and Eastern Europe), three acts, four scenes (primarily in Russia and Eastern Europe) or, more rarely, in two acts, four scenes.  Originally choreographed by Julius Reisinger to the music of Pyotr Ilyich Tchaikovsky (opus 20), it was first presented as "The Lake of the Swans" by the Ballet of the Moscow Imperial Bolshoi Theatre on 20 February/4 March 1877 (Julian/Gregorian calendar dates) in Moscow, Russia.  Although the ballet is presented in many different versions, most ballet companies today base their stagings both choreographically and musically on this revival by Marius Petipa and Lev Ivanov, staged for the Imperial Ballet, first presented on 15 January/27 January 1895, at the Imperial Mariinsky Theatre in St. Petersburg, Russia instead of the original version.

Carolina Ballet: Carolina Ballet is a ballet company founded in 1997 which performs primarily in Raleigh, North Carolina and throughout the state.  It has toured to New York City, Hungary and China.  Robert Weiss, the artistic director, danced for George Balanchine for sixteen years at New York City Ballet and attained the rank of principal dancer.  Lynne Taylor-Corbett is principal guest choreographer.  One of Carolina Ballet's most popular performances, The Nutcracker, is performed annually.  Carolina Ballet currently has about 35 dancers.

The Nutcracker: The Nutcracker (Russian: Щелкунчик, Балет-феерия / "Shchelkunchik, Balet-feyeriya"    ; French: "Casse-Noisette, ballet-féerie" ) is a two-act ballet, originally choreographed by Marius Petipa and Lev Ivanov with a score by Pyotr Ilyich Tchaikovsky (op. 71).  The libretto is adapted from E. T. A. Hoffmann's story "The Nutcracker and the Mouse King", by way of Alexandre Dumas' adapted story "The Nutcracker".  It was given its premiere at the Mariinsky Theatre in Saint Petersburg on Sunday, December 18, 1892, on a double-bill with Tchaikovsky's opera "Iolanta".

Le Réveil de Flore: Le Réveil de Flore (en.  "The Awakening of Flora"), (ru.  «Пробуждение Флоры», "Probuzhdenie Flory") is a "ballet anacréontique" in one act, with choreography by Marius Petipa and music by Riccardo Drigo, to a libretto written by Petipa and Lev Ivanov.  First presented by the Imperial Ballet at Peterhof Palace on 6 August [O.S. 25 July] 1894 .

Swan Lake (Martins): Swan Lake is a two-act ballet made by New York City Ballet (NYCB) ballet master in chief Peter Martins (after Marius Petipa, Lev Ivanov, and George Balanchine) to Tschaikovsky's eponymous music (1875–56).  The premiere took place 27 October 1996, with the Royal Danish Ballet at the Royal Theatre, Copenhagen; the NYCB premiere was 29 April 1999 at the New York State Theater, Lincoln Center.  Peter Martins' wife, NYCB principal dancer Darci Kistler, chose to include the final act of "Swan Lake" in her farewell performance, Sunday, 27 June.

Lev Ivanov: Lev Ivanovich Ivanov (Russian: Лев Ива́нович Ива́нов ; 2 March 1834, Moscow – 24 December 1901, Saint Petersburg) was a Russian ballet dancer and choreographer and later, Second Balletmaster of the Imperial Ballet.  As a performer with the Imperial Ballet, he achieved prominence after performing as an understudy in a benefit performance of "La Fille Mal Gardée".  He is most famous as the choreographer of "Dance of the Little Swans" from "Swan Lake", Act II of "Cinderella", and "The Nutcracker", which he choreographed alongside Marius Petipa.

Trilby (ballet): Trilby is a "ballet" in 2 acts and 3 scenes, with choreography by Marius Petipa and music by Yuli Gerber.  Libretto by Marius Petipa, based on the 1822 novella "Trilby, ou le lutin d'Argail " by Charles Nodier, first presented by the Ballet of the Moscow Imperial Bolshoi Theatre on January 25/February 6 (Julian/Gregorian calendar dates), 1870, in Moscow with Polina Karpakova as Trilby and Ludiia Geiten as Miranda and restaged by Petipa for the Imperial Ballet at the Imperial Bolshoi Kamenny Theatre on January 17–29, 1871 in St. Petersburg with Adèle Grantzow as Trilby and Lev Ivanov as Count Leopold.

Sergeyev Collection: The Sergeyev Collection is a collection of choreographic notation, music, designs for décor and costumes, theatre programs, photos and other materials that document the repertory of the Imperial Ballet (precursor of the Kirov/Mariinsky Ballet) of St. Petersburg, Russia at the turn of the 20th century.  The majority of the choreographic notations document with varying degrees of detail the original works and revivals of the renowned choreographer Marius Petipa, who served as "Premier Maître de ballet" of the St. Petersburg Imperial Theatres, as well as notation and music documenting the ballets of Lev Ivanov, who served as second "Maître de ballet".  Also included in the collection are choreographic notation documenting dances from various operas by both Petipa and Ivanov, respectively.

The Nutcracker and the Mouse King: "The Nutcracker and the Mouse King" (German: "Nussknacker und Mausekönig" ) is a story written in 1816 by German author E. T. A. Hoffmann, in which young Marie Stahlbaum's favorite Christmas toy, the Nutcracker, comes alive and, after defeating the evil Mouse King in battle, whisks her away to a magical kingdom populated by dolls.  In 1892, the Russian composer Pyotr Ilyich Tchaikovsky and choreographers Marius Petipa and Lev Ivanov turned Alexandre Dumas père's adaptation of the story into the ballet "The Nutcracker", which became one of Tchaikovsky's most famous compositions, and perhaps the most popular ballet in the world.

The Slave (Petipa/Pugni): The Slave Girl (a.k.a. L'Esclave) is a ballet "Divertissement" in 1 Act, choreographed by the Balletmaster Marius Petipa to the music of Cesare Pugni, first presented by the Imperial Ballet for the Imperial Court at the Hermitage Theatre, on April 27/May 9 (Julian/Gregorian calendar dates), 1868 in St. Petersburg, Russia.  It featured Lev Ivanov.

Supporting paragraphs: Carolina Ballet The Nutcracker
Answer: 1997