Oh, I guess I assumed i could. In the guide it talks about "per playthrough" and I assumed it counted across all saves. Thanks for clearing it up!
20k GS: 2/22/10 (Bioshock 2: Escape)
30k GS: 7/19/10 (Alan Wake: Bright Falls' Finest)
40K GS: 1/17/11 (Fable III: The Resistance)
50K GS: 8/3/11 (Dragon Age 2: Knowledgeable)
60K GS: 4/20/12 (Kinect Adventures: Shining Example)
70K GS: 3/30/13 (Bioshock: Infinite: Heartbreaker)