How much chocolate would you have to eat to get the same amount of caffeine found in two cups of regular coffee?

A typical 28-gram serving of a Milk Chocolate bar has about as much caffeine as a cup of decaffeinated coffee, although dark chocolate has about the same caffeine as coffee by weight. Some Dark Chocolate currently in production contains as much as 160 mg per 100 g - which is double the caffeine content of the highest caffeinated drip coffee by weight.