Please answer a question about the following article about Adult contemporary music:

Although dance-oriented, electronic pop and ballad-oriented rock dominated the 1980s, soft rock songs still enjoyed a mild success thanks to artists like Sheena Easton, Amy Grant, Lionel Richie, Christopher Cross, Dan Hill, Leo Sayer, Billy Ocean, Julio Iglesias, Bertie Higgins and Tommy Page. No song spent more than six weeks at #1 on this chart during the 1980s, with nine songs accomplishing that feat. Two of these were by Lionel Richie, "You Are" in 1983 and "Hello" in 1984, which also reached #1 on the Hot 100.

What was the longest that a song spent at #1 on the adult contemporary charts in the 1980s?
six weeks