Which department learned the calculation of perpetual calendar?

The calculation of perpetual calendar was not studied by any department, but was handed down from history.

Introduction:

The perpetual calendar is the oldest solar calendar in ancient legends of China. This calendar is named "perpetual calendar" to commemorate the achievements of its creator for ten thousand years.

The perpetual calendar used now is an almanac that contains or is suitable for several years. With the development of science and technology, modern perpetual calendars can display multiple sets of calendars such as solar calendar, lunar calendar and trunk calendar at the same time, and can also contain various functional information such as good luck, holidays and reminders. Its carriers include almanac publications, electronic products, computer software and mobile phone applications, which are very convenient for people to query and use. Ten thousand years is just a symbol, indicating a long time span.