Quantitative Sentiment Analysis of Lyrics in Popular Music

Popular music has been changing significantly over the years, revealing clear, audible differences when compared with songs written in other eras. A pop music composition is normally made of two parts—the tune and the lyrics. Here we use a digital humanities and data science approach to examine how lyrics changed between the 1950’s and the more recent years, and apply quantitative analysis to measure these changes. To identify possible differences, we analyzed the sentiments expressed in the songs of the Billboard Hot 100, which reflects the preferences of popular music listeners and fans in each year. Automatic sentiment analysis of 6,150 Billboard 100 songs covering all the years from 1951 through 2016 shows clear and statistically significant changes in sentiments expressed through the lyrics of popular music, generally towards a more negative tone. The results show that anger, disgust, fear, sadness, and conscientiousness have increased significantly, while joy, confidence, and openness expressed in pop song lyrics have declined.