How much caffeine does root beer pepsi and coca cola have?

This data came from the Center for Science in the Public Interest. Just giving credit (and blame, if any of the figures are incorrect) where it's due. All figures are for a 12 oz. serving (one can).

• Most root beer (including Barq's Diet Root Beer) has none; caffeine is not a natural ingredient in root beer, and has to be specifically added.
• Barq's Regular Root Beer has 23 mg. This may be what the slogan "Barq's has bite" refers to.
• Regular Coke (and Coke Zero, and Diet Pepsi) has 35 mg.
• Regular Pepsi has 38 mg.
• Diet Coke has 47 mg.

Suddenly the fanaticism of some Diet Coke drinkers makes a lot more sense; they've allowed their addition to caffeine to overwhelm the fact that their taste buds are telling them "this tastes vile." Doesn't explain Coke Zero, but Coke Zero isn't (quite) as foul as Diet Coke.