Oricon:

*4　－　*49,242　*,*49,242　Passion　宇多田ヒカル

compared to Be My Last whose first week sales were 80,000 copies... I really think that her peak has passed (look at her singles and their sales..) after she released Colors in 2003

* "Passion" (December 14, 2005) ? #4 over 49,000 copies sold (still charting)
* "Be My Last" (September 28, 2005) ? #1 over 145,000 copies sold
* "Dareka no Negai ga Kanau Koro" (April 21, 2004) ? #1 365,000 copies sold
* "Colors" (January 29, 2003) ? #1 894,000 copies sold
* "Sakura Drops/Letters" (May 9, 2002) ? #1 687,000 copies sold
* "Hikari" (March 20, 2002) ? #1 598,000 copies sold
* "Traveling" (November 28, 2001) ? #1 856,000 copies sold
* "Final Distance" (July 25, 2001) #2 582,000 copies sold
* "Can You Keep a Secret?" (February 16, 2001) ? #1 1,485,000 copies sold
* "For You/Time Limit" (June 30, 2000) ? #1 909,000 copies sold
* "Wait & See -Risk-" (April 19, 2000) #1 1,662,000 copies sold
* "Addicted to You" (November 10, 1999) ? #1 1,784,000 copies sold
* "First Love" (April 28, 1999) (12cm) ? #2 501,000 copies sold
* "First Love" (April 28, 1999) (8cm) ? #6 303,000 copies sold
* "Movin' on Without You" (February 17, 1999) (12cm) ? #1 880,000 copies sold
* "Movin' on Without You" (February 17, 1999) (8cm) ? #5 347,000 copies sold
* "Automatic/Time Will Tell" (December 9, 1998) (12cm) ? #2 1,291,000 copies sold
* "Automatic/Time Will Tell" (December 9, 1998) (8cm) ? #4 772,000 copes sold


Album sales have been decreasing as well~

* Utada Hikaru Single Collection Vol.1 (March 31, 2004) ? #1 2,544,000
* Deep River (June 19, 2002) ? #1 3,605,000 copies sold
* Distance (March 28, 2001) ? #1 4,467,000 copies sold
* First Love (March 10, 1999) ? #1 7,648,000 copies sold (worldwide: 10,000,000 copies sold) (Holds record for most copies of an album sold in Japanese history)

And she hasn't released an original Japanese album since 2002 (probably another root cause of this decreasing popularity).