Background: Born into a Bosniak family near Tuzla, SR Bosnia and Herzegovina, she grew up in Brcko, the youngest child of Abid Jahic (c. 1928 - 22 October 2010) and Ifeta (nee Smajlovic; 15 April 1934 - 21 November 2014). Both of her parents are originally from villages near Srebrenik; her father was born in Jezinac and her maternal family hailed from Cehaje. Fahreta grew up in a Muslim home with sister Faketa and brother Faruk. At the start of the Bosnian War in 1992, her sister Faketa escaped to Canada, where she lives today, while Brena stayed in Belgrade where she had been living since 1980.
Context: 1984 saw Brena and her band begin a cooperation with a new manager and producer, Raka Dokic. Bato, Bato, their third album, was released the same year. A new provocative image was accompanied by a new musical style, different from the one fostered by Popovic. Later that year, they held a concert in neighboring Romania, at the stadium in Timisoara to an audience of 65,000, what was at time among the most successful concerts of a Yugoslav musician outside their home country.  Their next three albums, Pile moje (1985) and Voli me, voli and Uske pantalone (both 1986) would propel her to the throne of the Yugoslav music scene. Along with these albums, Brena established a cooperation with Serbian folk star Miroslav Ilic and recorded a collaborative extended play Jedan dan zivota, which featured four songs, including a romantic duet called "Jedan dan zivota", and the song "Zivela Jugoslavija", which was received with a mixed response. The latter song was in line with Brena's only official political stance: an uncompromising support of a united Yugoslavia, with her becoming a symbol of this view. By the end of 1986, Lepa Brena had become the star of Belgrade social jet-set, and the most successful public figure in Yugoslavia.  Brena's manager Raka Dokic came up with the idea that her seventh studio album should be followed by a movie in which she would play the lead role. This idea was successfully implemented in 1987 when the motion picture Hajde da se volimo was filmed. The movie had the same name as the album. Many then-popular Yugoslav actors co-starred in the film, including Dragomir Gidra Bojanic, Milutin Karadzic, Velimir Bata Zivojinovic, Milan Strljic, etc. During the premiere of the film on 24 October 1987, Brena met her future husband, Serbian tennis star Slobodan Zivojinovic.  Based on the success of the original, two sequels were produced: Hajde da se volimo 2 (1989) and Hajde da se volimo 3 (1990), which was followed by the studio album Boli me uvo za sve. Boli me uvo za sve also had multiple hit songs including "Cik pogodi", "Bice belaja", "Tamba Lamba", and the title track. Their eighth studio album Cetiri godine was released on 1 October 1989 and contained the controversial song Jugoslovenka with Bosnian rock musician Alen Islamovic. The music video for the pop-folk song Cuvala me mama was filmed on the Croatian island Lopud.  Lepa Brena and Slati Greh held more than 350 concerts yearly, and would often hold two concerts in one day. They set a record by holding thirty-one concerts consecutively at Dom Sindikata, and seventeen concerts consecutively at the Sava Center. On 24 July 1990, Brena was lowered with a helicopter at Levski stadium in Sofia, Bulgaria, and held her then-most-attended concert with an audience of 110,000 people. While she was in Bulgaria in July 1990, she met with the Bulgarian mystic Baba Vanga.
Question: How many years did these concerts take place?

Answer: