How much caffeine is in decaffeinated coffee?

All decaffeination processes are performed on unroasted (green) coffee beans, but the methods vary somewhat. It generally starts with the steaming of the beans. They are then rinsed in solvent that contains as much of the chemical composition of coffee as possible without also containing the caffeine in a soluble form. The process is repeated anywhere from 8 to 12 times until it meets either the international standard of having removed 97% of the caffeine in the beans or the EU standard of having the beans 99.9% caffeine free by mass. Coffee contains over 400 chemicals important to the taste and aroma of the final drink; this effectively means that no chemical reaction will remove only caffeine while leaving the other chemicals at their original concentrations. While they are occasionally referred to informally as "decaffeinated," soft drinks without caffeine are prepared by simply leaving caffeine out in the first place.