It is a pity that this week's The Division drop was a bit higher than in these past weeks.
DiRT 3 sold 54,000 units in its launch week and DiRT 2 sold less although I can't give an approximate figure.
Dirt Showdown was one spot above Fifa 12 which sold around 7,000 units that week.
Week 21, 2012 Individual Formats
08 (NE) 360 DIRT SHOWDOWN (CODEMASTERS) < 5,600
09 (NE) 3DS MARIO TENNIS OPEN (NINTENDO)
10 (09) 360 [PROTOTYPE 2] (ACTIVISION BLIZZARD)
11 (06) 360 SNIPER ELITE V2 (505 GAMES)
12 (07)
360 FIFA 12 (ELECTRONIC ARTS) ~ 3,600
13 (NE) PS3 DIRT SHOWDOWN (CODEMASTERS) < 3,600
https://www.theguardian.com/technology/gamesblog/2012/may/28/top-20-video-games
DIRT SHOWDOWN < 9,200
DIRT RALLY < 27,300
Evidently these are approximations, very accurate but approximations, so the actual figures can be slightly off.