Sixty Years is the Heavenly Stems and Earthly Branches. The five elements in the zodiac are determined by the heavenly stems and earthly branches. Each zodiac sign has five elements. In other words, one zodiac sign has the five elements of metal, wood, water, fire, and earth, and the same zodiac sign has one type of five elements every 12 years. For example, the rat is the son in the zodiac. There are five ***, which are respectively with metal, wood, water, fire and earth. These five are: Jiazi (wood rat), Bingzi (fire rat), Wuzi (earth rat), Gengzi (gold rat), Ren Zi (water rat). Sixty Years means that an attribute of the same zodiac will come out every 12 years, and it will be sixty years (one round) until the same attribute comes out again. 12 (years) × 5 (five elements) = 60 years (one round).