According to Girls Gen Z Digital media company Sweety High's 2018 Gen Z Music Consumption & Spending Report, Spotify ranked first for music listening among Gen Z, terrestrial radio ranked second, while YouTube was reported to be the preferred platform for music discovery. Using artificial intelligence, Joan Serrà and his team at the Spanish National Research Council studied the massive Million Song Dataset and found that between 1955 and 2010, popular music has gotten louder, while the chords, melodies, and types of sounds used have become increasingly homogenized. Indeed, producers seem to be engaging in a "Loudness War", with the intention of attracting more and more audience members. Old hits are re-recorded with simpler chord progression and increased loudness using different instruments to sound new and fashionable. While the music industry has long been accused of producing songs that are louder and blander, this is the first time the quality of songs is comprehensively studied and measured. Additional research showed that within the past few decades, popular music has gotten slower; that majorities of listeners young and old preferred older songs rather than keeping up with new ones; that the language of popular songs was becoming more negative psychologically; and that lyrics were becoming simpler and more repetitive, approaching one-word sheets, something measurable by observing how efficiently lossless compression algorithms (such as the LZ algorithm) handled them.