Dominican folk music is an oral tradition, learned informally through watching others perform. As of 1987, most performers of traditional music were either over 50 years old or under 35, which indicates an ongoing revival of previously declining traditions. Music is evaluated based on both characteristics of the music, such as complex syncopated rhythms, as well as social factors, such as the ability of the performers to improvise and respond to their surroundings and to keep the audience excited and participating in the music.