Justin Bieber's #MusicMonday Series: A Progress Report

Five songs have been released so far with another five expected weekly through mid-December.

As Justin Bieber's Music Monday series reaches its halfway point, let's assess how it's doing thus far.

Since his song "Heartbreaker" hit digital retail in the evening of Sunday, Oct. 6, Bieber has released a total of five songs, every Monday. Five more tunes are expected to be released weekly, through mid-December. On Christmas Day, Bieber's concert documentary, Believe, opens in movie theaters nationwide.  

None of the tracks have been officially promoted to radio, or are considered proper singles by Bieber's record label, Island. (They are also, at this point, not part of a future album release from the star.)

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Despite the lack of airplay, the five songs have debuted on the Billboard Hot 100 chart from the strength of their sales and streams. The first tune, "Heartbreaker," went the highest on the chart, reaching No. 13. (The Hot 100's formula combines sales, streams and airplay to determine the 100 most-popular songs of the week in the U.S., according to Nielsen data.)

In its first eight days on sale, "Heartbreaker" sold 182,000 downloads according to Nielsen SoundScan. That combines its Sunday evening sales from Oct. 6 with its first full week between Oct. 7-13.

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It was followed by "All That Matters" (127,000 in its debut, bowing at No. 24 on the Hot 100), "Hold Tight" (111,000; No. 29), "Recovery" (94,000; No. 41) and, this week, "Bad Day" (86,000; No. 53). Each song spent one week on the chart except for "Heartbreaker," which hung on for two.

Combined, the five songs have sold 720,000 downloads.

Notably, with the debut of "Bad Day" on the Hot 100 this week, Bieber's total number of entries on the ranking rises to 40.

This story first appeared on Billboard.com.