Please read the following table in Markdown format and then answer the question according to the table. Table cells in one row are seperated by '|', and different rows are seperated by '
'.

Table:
| Year | Cast\n(Nabucco, Abigaille, Zaccaria, Ismaele, Fenena) | Conductor,\nOpera House and Orchestra | Label |
| --- | --- | --- | --- |
| 1951 | Paolo Silveri,\nCaterina Mancini,\nAntonio Cassinelli,\nMario Binci,\nGabriella Gatti | Fernando Previtali,\nOrchestra Sinfonica e Coro di Roma della RAI | Audio CD: Warner Fonit\n8573 82646-2 |
| 1965 | Tito Gobbi,\nElena Souliotis,\nCarlo Cava,\nBruno Prevedi,\nDora Caral | Lamberto Gardelli,\nVienna State Opera Orchestra and Chorus | Audio CD: Decca\nCat: 417 407-2 |
| 1977–78 | Matteo Manuguerra,\nRenata Scotto,\nNicolai Ghiaurov,\nVeriano Luchetti,\nElena Obraztsova | Riccardo Muti,\nPhilharmonia Orchestra and the Ambrosian Opera Chorus | Audio CD: EMI Records\nCat: 747 488-2 |
| 1982 | Piero Cappuccilli,\nGhena Dimitrova,\nEvgeny Nesterenko,\nPlácido Domingo,\nLucia Valentini Terrani | Giuseppe Sinopoli,\nDeutsche Oper Berlin | Audio CD: DG\nCat: DG 410 512-2 |
| 1987 | Renato Bruson,\nGhena Dimitrova,\nPaata Burchuladze,\nBruno Beccaria,\nRaquel Pierotti | Riccardo Muti,\nLa Scala, Milan Orchestra and Chorus | DVD: Warner\nCat: 5050467-0944-2-0 |
| 2002 | Juan Pons,\nMaria Guleghina,\nSamuel Ramey,\nGwyn Hughes Jones,\nWendy White | James Levine,\nMetropolitan Opera | DVD: DG, live recording\nCat: B0006O9M6S |
| 2004 | Alberto Gazzale,\nSusan Neves,\nOrlin Anastassov,\nYasuharu Nakajiima,\nAnnamaria Popescu | Riccardo Frizza,\nTeatro Carlo Felice Orchestra and Chorus | DVD: Dynamic, live recording\nCat: 33465 |
| 2004 | Renato Bruson,\nMaurizio Frusoni,\nLauren Flanigan,\nCarlo Colombara,\nMonica Bacelli | Paolo Carignani,\nTeatro San Carlo Naples Orchestra and Chorus | DVD: Brilliant Classics, live recording\nCat: 92270 |
| 2007 | Leo Nucci,\nMaria Guleghina,\nCarlo Colombara,\nFabio Sartori,\nNino Surguladze, | Daniel Oren,\nArena di Verona Orchestra and Chorus | DVD: Decca, live recording\nCat: DDD 0440 074 3245 7 DH |
Question:
how many recordings of nabucco have been made?
Answer:
9