According to what calendar is the constellation calculated?

Constellations originally did not exist in China, but spread abroad, and there was no China lunar year in foreign countries, so constellations were calculated according to the public year, that is, the solar calendar (for example,1August 8, 988). You are March 36, and you need to calculate according to the year of birth. Now the old calendar is usually around one month, which is Taurus.