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Analysis of surviving astronomical records inscribed on oracle bones reveals a Chinese lunisolar calendar, with intercalation of lunar months, dating back to theShang Dynastyof the fourteenth century BC. Various intercalation schemes were developed for the early calendars, including the nineteen-year and 76-year lunar phase cycles that came to be known in the West as the Metonic cycle and Callipic cycle.

From the earliest records, the beginning of the year occurred near the winter solstice when a New Moon appeared, but the choice of month for the beginning of the civil year varied with time and place. In the late second century BC, a calendar reform established the practice, which continues today, of requiring the winter solstice to occur in the 11th month. This reform also introduced the intercalation system in which the dates of the New Moons are compared with the 24 solar terms. However, calculations were based on the mean motions resulting from the cyclic relationships. Inequalities in the Moon's motions were incorporated as early as the seventh century AD, but the Sun's mean longitude was used to calculate the solar terms until 1644.

Years were counted from a succession of eras established by reigning emperors. Although the accession of an emperor would mark a new era, an emperor might also declare a new era at various times within his reign. The introduction of a new era was an attempt to reestablish a broken connection between Heaven and Earth, as personified by the emperor. The break might be revealed by the death of an emperor, the occurrence of a natural disaster, or the failure of astronomers to predict a celestial event such as an eclipse. In the latter case, a new era might mark the introduction of new astronomical or calendar models.

Sixty-year cycles were used to count years, months, days, and fractions of a day using the set of Celestial Stems and Terrestrial Branches. While the use of the sixty-day cycle can be seen as far back as the earliest astronomical records, the sixty-year cycle was introduced in the first century AD or possibly a century earlier. Although the practice of counting the days according to the lunar calendar has fallen into disuse in everyday life, it is still tabulated in calendars. The initial year of the current year cycle began on February 2, 1984, which is the third day of the day cycle.