Sorry to keep quoting GAF in these threads, but this guy does some really good work comparing numbers:
http://www.neogaf.com/forum/showpost.php?p=69339206&postcount=2
[PS2] Simple 2000 Series Vol. 31: The Earth Defense Force (D3 Publisher) {2003.06.26} - 10.244 / 70.033
[PS2] Simple 2000 Series Vol. 81: Earth Defense Force 2 (D3 Publisher) {2005.07.28} - 41.974 / 195.880
[PS2] Simple 2000 Series Vol. 103: Global Defence Force Tactics (D3 Publisher) {2006.07.25} - ?
[360] Earth Defense Force 2017 (D3 Publisher) {2006.12.14} - 11.969 / 27.087
[360] Earth Defense Force 2017 (Xbox 360 Platinum Collection) (D3 Publisher) {2007.11.01} - 5.691 / 38.784
[PSP] Earth Defense Force 2 Portable (D3 Publisher) {2011.04.07} - 54.812 / 112.486
[PS3] Earth Defence Force: Insect Armageddon (D3 Publisher) {2011.07.07} - 30.224 / 57.526
[360] Earth Defence Force: Insect Armageddon (D3 Publisher) {2011.07.07} - 11.902 / 17.717
[PSV] Earth Defense Force 3 Portable (D3 Publisher) {2012.09.27} - 29.875 / 38.720
[PS3] Earth Defense Force 2025 (D3 Publisher) {2013.07.04} - 127.763 / NEW
[360] Earth Defense Force 2025 (D3 Publisher) {2013.07.04} - 16.499 / NEW
Biggest second week sales (PS Vita):
[PSV] Toukiden (Koei Tecmo) {2013.06.27} - 37.340 / 165.084 (-71%)
[PSV] Soul Sacrifice (Sony Computer Entertainment) {2013.03.07} - 26.561 / 132.424 (-75%)
[PSV] Persona 4 Golden (Atlus) {2012.06.14} - 18.069 / 170.568 (-88%)
[PSV] Hot Shots Golf 6: World Invitational (Sony Computer Entertainment) - 17.166 / 68.743 (-68%)
[PSV] Hatsune Miku: Project Diva f (Sega) {2012.08.30} - 16.807 / 174.816 (-89%)
EDF 2017 really came out at both the wrong time and on the wrong platform. Wonder what it would've sold as a PS2/Wii release.
Shows how impressive Toukiden's second week was as well. A good 10k higher than any other 2nd week sales on the platform.
