What does 99 on the calendar mean?

Jiujiu is a general term used by ancient people in China to indicate the date of 81 days after the winter solstice or summer solstice. Eighty-one days after the winter solstice is called "Winter 99" and eighty-one days after the summer solstice is called "Summer 99". This term is still very popular today. And folk generally refers to winter 99. Every nine days is a nine, which is called the ninth day, the second day, the third day, until the ninth day, which is called "counting nine cold days". This is for the winter in climate.

Summer 99 is usually compiled into agricultural proverbs according to climate change: for example, "the summer solstice enters the ninth day, and the feather fan is in hand;" In 29 18, I took off my crown and put on a scarf; On March 27, I went out to sweat; Four, nine, thirty-six, open-air rolling seats; In 5945, autumn was like a tiger; 6954, enter the temple to enjoy the cool; 7963, touching the sheets at the bedside; 8972, looking for a quilt in the middle of the night; 998 1, open the cupboard to get cotton-padded clothes. "

Extended data

Calculation method:

The non-healing day from the winter solstice to winter (after the winter solstice, the first non-healing day is called "Jiao Jiu", which means the beginning of cold), every nine days is a "Jiu", the first nine days are called "Jiu Jiu", the last nine days are called "Er Jiu", and so on, until "Jiu Jiu" and "Jin Jiu Peach Blossom", the weather will be warm. As the saying goes, "Summer solstice is three years old and winter solstice is nine years old." . It is generally the coldest in April and September, which is the coldest period of the year; By the ninth five-year plan, the cold had disappeared and spring was blooming.

The correct algorithm of "counting nine" is to count from the first nonyl day after the winter solstice. Therefore, the specific date of "September" every year is not fixed, depending on the first nonyl day after the winter solstice. Another mistake is that the number nine is counted from the date of the winter solstice, so the specific time of nine is fixed every year from the date of the winter solstice, and each nine is fixed on the ninth day, 18 and the 27th day after the winter solstice. The algorithm of counting nine from winter to day is wrong.