<a href="/music/SKE48">SKE48</a>'s "Muishiki No Iro" earns the top spot by a huge margin on this week's Billboard Japan Hot 100 dated Jan. 8 to 14. The Nagoya-based girl group's 10th anniversary single sold 305,192 CDs in its first week of sales and racked up points mainly in the physical metrics, coming in at No. 1 for physical sales, No. 2 for look-ups, No. 3 for Twitter mentions, and No. 26 for radio airplay.

At No. 2 for physical sales this week is <a href="/music/Nogizaka46">Nogizaka46</a>, the official rival group of AKB48 and its many sister groups including SKE48. Nogizaka46's "Itsuka Dekiru Kara Kyou Dekiru" performed well in most metrics except radio airplay this week including downloads, streaming, look-ups and Twitter, rising 16-4 on the Japan Hot 100.

Downloads is the key word of this week's Japan Hot 100, which sees a proliferation of download-only or download-first songs boosting its overall volume and thus increasing its share compared to most weeks. Songs that have charted in the top 20 without depending on physical metrics include this week's most-downloaded song, "ONE DAY" by Ryuji Imaichi, at No. 3; <a href="/music/lisa/chart-history/japan-hot-100">LiSA</a>'s "Thrill, Risk, Heartless" at No. 5; <a href="/music/TWICE">TWICE</a>'s "Candy Pop" at No. 10 and "TT" at No. 11; <a href="/music/Hikaru-Utada">Hikaru Utada</a>'s "Anata" at No. 15; <a href="/music/Bruno-Mars">Bruno Mars</a> and <a href="/music/Cardi-B">Cardi B</a>'s "Finesse" at No. 17; <a href="/music/Sambomaster">Sambomaster</a>'s "Dekikkonai Wo Yaranakucha" at No. 19; and PANDORA feat. <a href="/music/Beverly/chart-history/japan-hot-100">Beverly</a>'s "Be the One" at No. 20.

The songs in the upper ranks were assisted by Twitter points and have a good chance of becoming long-running hits depending on how well they fare in video views and streaming in the coming weeks.

Yoko Oginome's "Dancing Hero" drops two notches to No. 6 on this week's Japan Hot 100, but logs a fourth week at No. 1 for video views. This 30-plus-year-old resurgent disco hit maintained its reign over video views through the veteran singer's exposure on year-end TV specials. During these four weeks, the song's performance has shifted 6-6-20-23 in downloads and 3-3-7-5 in streaming, gradually losing momentum in the new year. How much longer the song and artist enjoy their current revival depends on these two metrics as TV programs settle back into their regular programming.

The Billboard Japan Hot 100 combines physical and digital sales, radio airplay, Twitter mentions, YouTube and GYAO! video views, Gracenote look-ups and audio streams from Apple Music, AWA, Google Play Music, KKBOK, LINE MUSIC, Rakuten Music, Recochoku provided by Gfk Japan, as well as streaming counts based on lyrics displayed on PetitLyrics.

Watch the "Muishiki No Iro" music video:

<iframe width="560" height="315" src="https://www.youtube.com/embed/so2ELIW3p48" frameborder="0" allow="autoplay; encrypted-media" allowfullscreen></iframe>

Billboard Japan Hot 100 Top 20 (dated Jan. 8 to 14)

1. Muishiki No Iro / SKE48

2. Kaze Ni Fukaretemo / Keyakizaka46

3. ONE DAY / RYUJI IMAICHI

4. Itsuka Dekiru Kara Kyou Dekiru / Nogizaka 46

5. Thrill, Risk, Heartless / LiSA

6. Dancing Hero / Yoko Oginome

7. NO DOUBT / Re:vale

8. Mabataki / back number

9. Hero / Namie Amuro

10. Candy Pop / TWICE

11. TT / TWICE

12. Uchiage Hanabi / Daoko X Kenshi Yonezu

13. Fukyouwaon / Keyakizaka46

14. Reboot / TVXQ

15. Anata / Hikaru Utada

16. MIRAI / SOLIDEMO

17. Finesse Feat. Cardi B / Bruno Mars

18. Tomoni / WANIMA

19. Dekikkonai Wo Yaranakucha / Sambomaster

20. Be The One / PANDORA feat. Beverly