The Bills won consecutive AFL Championships in 1964 and 1965, the only major professional sports championships from a team representing Buffalo. After joining the NFL, they became perennial postseason contenders during the late 1980s and 1990s. Their greatest success occurred between 1990 and 1993 when they appeared in a record four consecutive Super Bowls; an accomplishment often overshadowed by them losing each game. From 2000 to 2016, the Bills endured the longest active playoff drought of the four major North American professional sports, making them the last NFL franchise and the last in the four leagues to qualify for the postseason in the 21st century. They returned to consistent postseason contention by the late 2010s, although the Bills have not returned to the Super Bowl. Alongside the Minnesota Vikings, their four Super Bowl losses are the most among NFL franchises that have not won the championship.