Example
§500 mg tablets of Ampicillin.
§The DDD for Ampicillin is 2.0 g per day
§2.0 g/500 mg = 4. That is, 4 tablets are required to make up 1 DDD.
§如果一年內有3,000,000 tablets 被處方, then
§   the # of DDDs would be 3,000,000 tablets/4 tablets per DDD = 750,000 DDDs per year.