Why doesn't the perpetual calendar match the old yellow calendar?

"Ten thousand years" in the perpetual calendar means a long time span, but it doesn't really mean ten thousand years, but the time recorded in the perpetual calendar is still longer than that recorded in the Gregorian calendar, including at least 100 years of Gregorian calendar, lunar calendar, calendar, Tibetan calendar and other calendars, as well as information related to the Gregorian calendar, such as good luck and bad luck, holidays and reminders.

Generally, the yellow calendar is printed and published on a yearly basis, and many calendars such as solar calendar, lunar calendar and dry calendar can also be displayed, with a large number of rules and contents related to seeking good fortune and avoiding evil.

The yellow calendar belongs to a kind of perpetual calendar. Perpetual calendar: The oldest solar calendar in ancient legends in China, which records the dates of specific solar calendars and lunar calendars within a certain time range (such as 100 or longer) for the convenience of people in need. Ten thousand years is just a symbol, indicating a long time span.

Extended data:

In modern times, the main contents of the yellow calendar include: Gregorian calendar, lunar calendar and trunk calendar, as well as trunk calendar, twenty-four solar terms, twelve gods, week, orientation and so on. In other words, people in ancient China recorded their daily likes and dislikes on calendars as a guide to action.

China's traditional calendar is based on heavenly stems and earthly branches's arrangement, combination and circulation, which means circulation and reappearance. It is this reappearance that makes it meaningful to choose a date to avoid it. The fundamental basis for the ancients to make calendars and determine auspicious days was the sun, the moon and the stars.

Baidu Encyclopedia-Huangli

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