Naming Vietnamese Lunar Years (Âm Lịch Việt Nam)
The year of the Dragon lasted from January 23, 2012 until February 10, 2013, when it was replaced by the year of the snake. The past year that was dynamic and powerful as the Dragon itself was Nhâm Thìn, the new one is Quý Tỵ, as provided by the Vietnamese Lunar Calendar.
As naming the years is not as popular in other parts of the world, things for them might appear a little complicated to put together regarding how the years are named.
Whereas the previous year (2011) was called Tân Mão and how the following year’s name of Quý Tỵ (year 2013) is already figured out, the system of naming the years along with the cycles in the Lunar calendar would, in reality, only require a few basic understanding of this remarkably interesting calendar.
Naming a Vietnamese year is basically done by combining two cycles, the "Ten Heavenly Stems" and the "Twelve Earthly Branches".
Twelve Earthly Branches
The "Twelve Earthly Branches" ("shi er di zhi") denotes the twelve signs of the zodiac consisting of: Tý (Rat), Sửu (Ox/Buffalo), Dần (Tiger), Mẹo/Mão (Cat/Rabbit), Thìn (Dragon), Tỵ (Snake), Ngọ (Horse), Mùi (Sheep/Goat), Thân (Monkey), Dậu (Chicken), Tuất (Dog) and the Hợi (Pig/Boar).
Ten Heavenly Stems
Meanwhile, the "Ten Heavenly Stems" ("shi tian gan" ...), comprised of Giáp, Ất, Bính, Đinh, Mậu, Kỷ, Canh, Tân, Nhâm and Quý
are further associated with the concept of Yin and Yang as well as of with the five "Basic Elements" where Giáp and Ất belongs to "Wood", Bính and Đinh to "Fire", Mậu and Kỷ to "Earth", Canh and Tân to "Metal", and Nhâm and Quý to the element "Water". In relation to the two basic properties "yang" (Am) and "yin" (Duong), Giáp, Bính, Mậu, Canh and Nhâm are known to hold the qualities of "yang", while Ất, Đinh, Kỷ, Tân and Quý possess the "yin" qualities.
Naming the year
So putting two and two together, combining this year’s heavenly stem (Canh) in parallel with its property (Yang) and Basic Element (Metal) to its earthly body Dragon (Thìn), 2012 Nhâm Thìn is labeled as "Yang Water Dragon".
Combining in a round-robin manner the two shorter cycles of the "Can", or the ten-year cycle denoting the "Ten Heavenly Stems" and the "Ky" or the twelve-year cycle in congruent with the "Twelve Earthly Branches", a greater cycle of 60 years is formed. Derived from the least common multiple of 10 and 12, the 60-year cycle (called Can Chi) is more like how the centuries are divided into every 100 years.
As it cycles continuously, a particular year will return every after 60-year period. Each year in the Can Chi corresponds to a particular year name as follows:
Giáp Tý Ất Sửu Bính Dần Đinh Mão Mậu Thìn Kỷ Tỵ Canh Ngọ Tân Mùi Nhâm Thân Quý Dậu Giáp Tuất Ất Hợi Bính Tý Đinh Sửu Mậu Dần Kỷ Mão Canh Thìn Tân Tỵ Nhâm Ngọ Quý Mùi Giáp Thân Ất Dậu Bính Tuất Đinh Hợi Mậu Tý Kỷ Sửu Canh Dần Tân Mão Nhâm Thìn Quý Tỵ Giáp Ngọ Ất Mùi Bính Thân Đinh Dậu Mậu Tuất Kỷ Hợi Canh Tý Tân Sửu Nhâm Dần Quý Mão Giáp Thìn Ất Tỵ Bính Ngọ Đinh Mùi Mậu Thân Kỷ Dậu Canh Tuất Tân Hợi Nhâm Tý Quý Sửu Giáp Dần Ất Mão Bính Thìn Đinh Tỵ Mậu Ngọ Kỷ Mùi Canh Thân Tân Dậu Nhâm Tuất Quý Hợi
Used in China since the second millennium B.C. as its manner of naming their days (pretty much how the Western world names the days of their week). The method utilizing the Sexagenary (Stem-Branches) cycle is evident throughout the Zhou dynasty as their records were found to be written in such manner. Its popularity is seen much widely around 202 BC-8 A.D. during the period of Western Han Dynasty. How and when it was adopted by several other East Asian countries (Japan, Korea, Vietnam...) varied throughout history.
Since a particular year returns after every Can Chi or passing sexagenary cycle, a year that began in 1984 will therefore enter a new cycle by year 2044. In the same manner, the previous Nhâm Thìn took place during 1952 which is exactly 60 years from today. When this cycle ends, the next Tân Mão, then, won’t be around until year 2072.