In what year did People's Republic of China (PRC) Pharmacopoeia start to be divided into four parts?

People's Republic of China (PRC) Pharmacopoeia 20 15 is divided into four parts. According to relevant public information, People's Republic of China (PRC) Pharmacopoeia was first published in 1953, and only a part of it was published at that time. In the future, it will be revised and upgraded every once in a while, and new contents and specifications will be added continuously. China People's Pharmacopoeia 1990 is divided into two parts: one part is chemical medicine and the other part is Chinese medicine. People's Republic of China (PRC) Pharmacopoeia (2000 edition) began to be divided into three parts: traditional Chinese medicine, chemical medicine and biological products. The 20 15 edition of China People's Pharmacopoeia is divided into four parts: traditional Chinese medicine, chemical medicine, biological products and pharmaceutical excipients.