GTA IV sales may have slumped by 70% according to reports from data gatherers Chart Track, but that still hasn't stopped Rockstar's title outselling Wii Fit by 4 units to 1 and retaining first place in this week's multi-format charts.

There's little movement in the top 20 this week, with the only significant mover being Iron Man which has risen up the charts into the top 10, placing at number 4 this week.

Multi-format video games chart for week ending 9th May

1 GRAND THEFT AUTO IV
2 WII FIT
3 MARIO & SONIC AT THE OLYMPIC GAMES
4 IRON MAN: THE OFFICIAL VIDEOGAME
5 CALL OF DUTY 4: MODERN WARFARE
6 PRO EVOLUTION SOCCER 2008
7 MARIO KART WII
8 GUITAR HERO III: LEGENDS OF ROCK
9 TOM CLANCY'S RAINBOW SIX: VEGAS 2
10 COOKING MAMA 2
11 FIFA 08
12 - UEFA EURO 2008 AUSTRIA-SWITZERLAND
13 HALO 3
14 SEGA SUPERSTARS TENNIS
15 NEW SUPER MARIO BROS.
16 MARIO KART DS
17 ASSASSIN'S CREED
18 LEGO STAR WARS: THE COMPLETE SAGA
19 FOOTBALL MANAGER 2008
20 SUPER MARIO GALAXY

You can check out reviews of the Top 5 games this week below:

GRAND THEFT AUTO IV Review
WII FIT Review
MARIO & SONIC AT THE OLYMPIC GAMES Review