Puerh History - Pu-erh.Net

„Yunnan Tea Company standardized the trade number for Pu Erh Tea in 1976 for the purpose of export. Each bingcha has 4 digits: the first 2 digits indicate the manufacturing year, the third digit indicates the leaf grade, the last digit indicates the tea factory (e.g. Kun-Ming 1, Meng-Hai 2, Xia-Guan 3, Pu Erh 4). The loose-leaf tea has 5 digits with the third and fourth indicating the class level of raw materials. Examples of early trade numbers for Puerh Tea are 7452, 7562, 7572, 75671, 76563.“

„cha yi; 茶仪 - Tea ceremony. Not generally used to refer to the daily habit of tea making and drinking. Most habitual tea drinkers would be unlikely to use this term in reference to their tea-making activities. Not common parlance in Yunnan tea making circles“