A new study from the Royal Society Open Science has looked at of hundreds of thousands of popular songs over the past three decades - and the findings aren't that cheery, Overall, pop music has seen a dramatic trend downward in happiness and an increase in sadness.

Researchers at the University of California at Irvine looked at 500,000 songs released in the UK between 1985 and 2015 and then categorized them according to their mood. Interestingly, the "happy" quality in songs was on the decline, but the sonic tendencies for "dance" and "party" music was going up - a vibe that you would think would lead towards happiness. This study did not specifically look at lyrical shifts, but researchers say the musical trend aligns with lyric changes found in other studies as well. The ideas of loneliness, isolation and anxiety have all become larger features of pop songs as a whole.

Some of the songs with a low happiness index include “Stay With Me” by Sam Smith, “Whispers” by Passenger and “Rolling In the Deep" by Adele. “The public seems to prefer happier songs, even though more and more unhappy songs are being released each year,” the researchers wrote. The most successful genres of music continue to be dance and pop, with a “clear downward trend” for rock music in the early 2000s.