Given this paragraph about the history of the Calgary Flames hockey team, what year did the Calgary Flames win their only Stanley Cup

The team was founded in 1972 in Atlanta as the Atlanta Flames before relocating to Calgary in 1980. The Flames played their first three seasons in Calgary at the Stampede Corral before moving into the Scotiabank Saddledome (originally the Olympic Saddledome) in 1983. In 1985–86, the Flames became the first Calgary team since the 1923–24 Tigers to compete for the Stanley Cup. In 1988–89, the Flames won their first and only Stanley Cup title. The Flames' unexpected run to the 2004 Stanley Cup Finals gave rise to the Red Mile, and in 2011, the team hosted and won the second Heritage Classic outdoor game.

The Calgary Flames won their only Stanley Cup in 1989