BTS fans had a slew of surprises bestowed upon them last week, including the group's leader RM delivering a new solo release that makes its way onto the Billboard 200.

RM's Mono. (which was labeled a "playlist" on the cover art) was released for free download as well as via digital-download and streaming services on Tuesday, Oct. 23. With less than three days of chart activity, Mono. debuts at No. 26 on the Billboard 200 with 21,000 equivalent album units earned in the week ending Oct. 25, according to Nielsen Music. Of that sum, 16,000 were in traditional album sales.

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The Billboard 200 chart ranks the most popular albums of the week in the U.S. based on multi-metric consumption as measured in equivalent album units. Units are comprised of traditional album sales, track equivalent albums (TEA) and streaming equivalent albums (SEA). The new Nov. 3-dated chart -- where RM debuts and the A Star Is Born soundtrack spends its third week at No. 1 -- will be posted in full on Billboard's websites on Tuesday, Oct. 30, along with the rest of Billboard's weekly charts dated Nov. 3.