Jia Zi

Ju = Situation The Earliest situation in this sense was 117 B.C. = Jia Zi
Since the numbers 10 (Heavenly Stems) and 12 (Earthly Branches) have a common factor of 2, only 1/2 of the 120 possible stem-branch combinations actually occur. The resulting 60-year (or sexagesimal) cycle takes the name jiazi after the first year in the cycle, being the Heavenly Stem of "jia" and Earthly Branch of "zi". The term "jiazi" is used figuratively to mean "a full lifespan"—one who has lived more than a jiazi is obviously blessed