The average speed of an artist's music decreases as they get older.
Dolly Parton's music has got slower over the years
Geoff Luck, an expert from the University of Jyvaskyla in Finland, has analysed more than 14,000 songs on Spotify from artists whose careers have spanned for at least 20 years - including Pearl Jam, Cyndi Lauper and Dolly Parton - and found that the average tempo of their tunes declined by about two beats per minute (bpm) for each decade aged.
Luck suggests that the "unconscious" drop in speed reflects how the body and mind reduce in terms of pace as people age.
He said: "I would suspect it's something happening for most artists unconsciously.
"We know that as we age, we tend to slow down. Cognitively, but also physically. In particular, our motor competence degrades as we age. So we can't move as fast or as accurately."
Tagged in Cyndi Lauper Dolly Parton