Biggest second week drop
inside the Famitsu Top 30 since 1996:
2015-05-04 [WII] Dragon Quest X: Inishie no Ryuu no Denshou Online (Square Enix) - 3,883 / 88,068 / -95.388%
2015-05-04 [WIU] Dragon Quest X: Inishie no Ryuu no Denshou Online (Square Enix) - 4,490 / 101,814 / -95.387%
2013-09-02 [PS3] Final Fantasy XIV: A Realm Reborn (Square Enix) - 11,835 / 196,297 / -93.584%
2004-11-08 [XBX] Dead or Alive: Ultimate (Tecmo) - 3,603 / 56,004 / -93.124%
2013-07-29 [PS3] Dragon's Crown (Atlus) - 7,701 / 116,732 / -92.937%
2011-06-20 [360] Steins;Gate: Hiyoku Renri no Darling (5pb.) - 2,974 / 43,447 / -92.652%
2013-09-02 [PS3] JoJo's Bizarre Adventure All-Star Battle (Bandai Namco) - 30,194 / 421,777 / -92.289%
2012-02-20 [3DS] New Love Plus (Konami) - 8,961 / 119,355 / -91.883%
2012-03-19 [PSP] Puella Magi Madoka Magica Portable (Bandai Namco) - 6,049 / 78,575 / -91.660%
2003-04-21 [PS2] Final Fantasy XI: Rise of the Zilart - Expanded Data Disk (Square Enix) - 8,699 / 105,806 / -91.042%
The majority of them being since 2012 is due to the dying retail sales in Japan, which lowers the threshold necessary for appearance inside the top 30.
There are games that have dropped worse than the DQX expansion but had the second week
outside the top 30, such as:
2002-08-12 [NGB] Dragon Ball Z: Legendary Super Warriors (Banpresto) - 1,203 / 33,601 / -96.287%
But they're probably sold-out titles. We don't know if DQX is sold-out or is simply a case of everyone who wanted it bought on release. (Note the MMO presence.)
Calling it now.
Next week is going to be the worst week ever in the japanese game history.
Quoting myself. Another record low probably coming.
Famitsu, there's only one week that is worse since 1997, and these are all were the no. 1 is below 20k
2003-05-12 [GBA] Fire Emblem: Rekka no Ken - 15,426 / 190,904
2015-04-06 [PS4] Dark Souls II: Scholar of the First Sin - 16,047 / 16,047
2011-05-09 [NDS] Dragon Quest Monsters: Joker 2 Professional - 17,995 / 400,736
2000-05-15 [N64] Kirby 64: The Crystal Shards - 18,571 / 542,443
Looking forward to this year's May.