I'll give them score to show the gaps between the albums:
1. The Marshall Mathers LP (100/100)
2. The Slim Shady LP (99/100)
3. Relapse (98/100)
4. The Eminem Show (97/100)
5. The Marshall Mathers LP 2 (80/100)
6. Encore (70/100)
7. Infinite (65/100)
8. Recovery (50/100)