Charting and release

"Why" debuted at number ten on the Oricon

Oricon

, established in 1999, is the holding company at the head of a Japanese corporate group that supplies statistics and information on music and the music industry in Japan. It started as , which was founded by Sōkō Koike in November 1967 and became known for its music charts. Oricon Inc...

 weekly chart, a top 100 songs and artists chart, selling 15,189 copies that week. The single charted for ten weeks and to date has sold approximately 29,000 copies. That month the title track debuted and peaked at number two on the RIAJ Digital Track Chart

RIAJ Digital Track Chart

The is chart ranks the best selling digital singles in Japan, provided by the Recording Industry Association of Japan since April 2009. The chart measures cellphone downloads ....

 behind "Futatsu no Kuchibiru" by Exile, before also being certified gold for full-length downloads. On the Billboard Japan Hot 100

Japan Hot 100

The Japan Hot 100 is a music singles chart in Japan. It is compiled by Billboard and Hanshin Contents Link ever since February 2008. The chart is updated every Wednesday at billboard-japan.com and every Thursday at billboard.com ....

, the title track peaked at number eight on the week November 24-30, 2009.

Charts

Released	Oricon Oricon , established in 1999, is the holding company at the head of a Japanese corporate group that supplies statistics and information on music and the music industry in Japan. It started as , which was founded by Sōkō Koike in November 1967 and became known for its music charts. Oricon Inc...  Chart	Weekly Peak	Debut Sales	Sales Total	Chart Run
November 18, 2009	Daily Singles Chart	7		29,089	10 weeks
	Weekly Singles Chart	10	15,189
	Monthly Singles Chart
	Yearly Singles Chart

Charts (2009)	Peak position
Japan (Oricon Singles Chart Oricon , established in 1999, is the holding company at the head of a Japanese corporate group that supplies statistics and information on music and the music industry in Japan. It started as , which was founded by Sōkō Koike in November 1967 and became known for its music charts. Oricon Inc... )	10
Japan (Japan Hot 100 Japan Hot 100 The Japan Hot 100 is a music singles chart in Japan. It is compiled by Billboard and Hanshin Contents Link ever since February 2008. The chart is updated every Wednesday at billboard-japan.com and every Thursday at billboard.com .... )	8
Japan (RIAJ Digital Track Chart RIAJ Digital Track Chart The is chart ranks the best selling digital singles in Japan, provided by the Recording Industry Association of Japan since April 2009. The chart measures cellphone downloads .... )	2