From my copy of "Sugar-Free Cooking with Stevia" (The book the FDA wanted burned):

1 cup Sugar
1 cup Sucralose
24 packets Stevia Blend
12 tsp. Spoonable Stevia Blend
2.5 tsp. Stevia Extract Liquid
1.5 tsp. PURE Stevia Extract Powder

NOTE: Not all Stevia Extract Powders are pure. Look for a 28 mg serving size or thereabouts... If the serving size is significantly larger, the Stevia isn't pure.