In what year did the song Symfonin reach top of the Swedish singles charts at the festival that has been the launch-pad for the success of popular local acts?  Answer the above question based on the context below:  Hundreds of songs and performers have entered Melodifestivalen since its debut. Although songwriters living outside Sweden were once not allowed to enter Melodifestivalen, the 2012 contest marked the first time foreign songwriters could submit entries, provided that they collaborated with a Swedish songwriter. To be eligible, songwriters and performers must be at least sixteen years of age on the day of the first Eurovision semi-final.Until 2001, participation in the festival was limited to a single night. The number of contestants ranged from five to twelve. A two-round system was used intermittently between 1981 and 1998, in which all but five of the contestants were eliminated in a first round of voting. Failure to reach the second round under this system was seen as a major failure for a prominent artist; when Elisabeth Andreassen failed to qualify in 1984, it almost ended her career. The introduction of weekly semi-finals in 2002 increased the number of contestants to thirty-two. At least ten of the contestants must perform in Swedish. A CD of each year's competing songs has been released since 2001, and a DVD of the semi-finals and final since 2003. Melodifestivalen has been the launch-pad for the success of popular local acts, such as Anne-Lie Rydé, Tommy Körberg, and Lisa Nilsson. The competition has played host to performers from outside Sweden, including Baccara, Alannah Myles, Katrina Leskanich, and Cornelis Vreeswijk. Melodifestivalen participants have also represented—and unsuccessfully tried to represent—other countries at Eurovision. While local success for Melodifestivalen winners is common, most contestants return to obscurity and few have major international success. The impact that the competition makes on the Swedish charts means an artist need not win the competition to earn significant domestic record sales. For example, the song which finished last at Melodifestivalen 1990, "Symfonin" by Loa Falkman, topped the Swedish singles chart. The most recent occurrence was 2016 with Samir &...
Answer:
1990