2020 on December 31, 2019 in New York City. BTS sends two old songs, “BTS Cypher 4” and "Ugh!," back to the World Digital Song Sales chart, with the former reaching a new all-time peak this week.

These days, whenever BTS has a new album to share with fans, the majority of the tracks featured on the set (if not all of them) find their way to Billboard’s World Digital Song Sales chart.

Even people who don’t listen to K-pop can name a few BTS songs, especially since they began releasing English-language hits like Dynamite, Butter and Permission to Dance. All these have climbed ...