From the 1946 movie of the same name, here’s Bing Crosby singing “Blue Skies.”

26 years later, here are The Allman Brothers performing “Blue Sky.”

Five years after that, Linda Ronstadt sang “Blue Bayou.”

Ten years earlier, Paul Mauriat recorded an orchestral version of a Eurovision 4th-place finisher called “Love is Blue.” It hit the Billboard Hot 100 chart and stayed #1 there for five weeks.

And finally, another instrumental. In the 1980s Mike Post composed the theme for the best cop show ever made for TV, “Hill Street Blues.”