The permutations and combinations of the Decimal Cycle (Heavenly Stems) and the Duodecimal Cycle (Earthly Branches) are usually used to mark a complete cycle of every sixty years. It is named the Ganjy system, also known as Jiahtzyy, a traditional way to reckon years in China. The Duodecimal Cycle (Earthly Branches) is represented by twelve species of animals including Rat, Ox, Tiger, Hare, Dragon, Serpent, Horse, Sheep, Monkey, Cock, Dog and Pig. Therefore, they are called the twelve Chinese Zodiac animals. 　　 The first set of New Year's Greeting Postage Stamps was issued in 1968. Since then, 24 sets of Chinese Zodiac Postage Stamps have been released. The monkey stamps issued on November 30, 1991, have just completed the two series cycle of Chinese Zodiac Postage Stamps. The second series of Chinese New Year's Greeting (Chinese Zodiac) Postage Stamps had concise and abstract sketches, roundness and a series which symbolized reunion every year. This Directorate composed these twelve stamps in order and released a set of stamps and a souvenir sheet (182×102 mm.) with face values of 5.00, in se-tenant of twelve stamps in two horizontal lines of six stamps each.