The U.S.P. was first published in 1820 and ever ten years thereafter until the Second World War, after which it has been revised every five years. It has always been meant to define the physical, chemical, and pharmaceutical characteristics of the most accepted and widely used drugs of the time, and to set the standards for purity. The N.E was first published in 1888, and, up until 1980, in the same year as the United States Pharmacopoeia. Since 1980, both have been issued in the same volume. The National Formulary was originally intended as a list of the official recipes for pharmaceutical formulas; characteristics of those drugs or plants used in the formulas or that were still recognised as secondary drugs; and the substances needed for the manufacturing of drugs but that were not active, like gelatin or pill binders.