ORS covered this entirely, but I'll just add my two cents. Pedro's stretch from 1997-2000 (and as ORS mentioned, possibly 1997-2003) was the greatest four year stretch ever.
219 ERA+
5.68 SO/BB
0.925 WHIP
If you want advanced stats his FIP in those four years was 2.39, 3.40, 1.39, and 2.17. Crazy good.