Researchers from Durham University analyzed Spotify data linked to some 4,500 songs that regularly featured on lullaby playlists created on the music streaming service.
In doing so, they were able to calculate the average beats per minute (BPM), most common key and time signatures, effectively creating the perfect formula for a lullaby.
The study concluded that U2's chart topping song from 1992, "One," contains all the properties of the “perfect lullaby”.