sam sadImage Source: endz2endz.com

The Royal Society Open Science by the University of California at Irvine has studied over 500,000 chart-topping songs released in the United Kingdom between 1985 to 2015 and grouped them according to the mood they evoke.

Their research found that a majority of popular songs had a significant shift in the “happiness” index over the past 30 years. According to co-author Natalia Komarova, “‘Happiness’ is going down, ‘brightness’ is going down, ‘sadness’ is going up, [but] at the same time [ironically], the songs are becoming more ‘danceable’ and more ‘party-like’.”

She added: “So it looks like, while the overall mood is becoming less happy, people seem to want to forget it all and dance.

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Despite the increase of sad-sounding pop hits like Stay with Me by Sam Smith and Let Her Go by Passenger, the researchers found that sadder songs weren’t necessarily more popular, writing: “The public seems to prefer happier songs, even though more and more unhappy songs are being released each year.

The research also added that a “clear downward trend” in the success of rock music in the charts has been observed starting the early 2000’s. They also said that “successful songs are characterized by a larger percentage of female artists” over the last 30 years.