How old is the post-90s pig this year?

This is because in the traditional culture of China, the nominal age is calculated according to the lunar calendar (the traditional calendar of China), that is, one year is added for every Lunar New Year (equivalent to New Year's Day in the Gregorian calendar). The first year of birth is calculated according to the Gregorian calendar, that is, the day from birth to 1 year is one year old. Therefore, there are some differences in calculation between nominal age and one year old.