Why do we set off firecrackers on the sixth day of the Lunar New Year? What is the sixth day of the Lunar New Year called?

Whenever the Spring Festival comes, the sound of firecrackers is continuous everywhere and it is very lively. In addition to setting off firecrackers on New Year's Eve, firecrackers are also set off on other days, such as the sixth day of the New Year. So why do we set off firecrackers on the sixth day of the Lunar New Year?

Why do we set off firecrackers on the sixth day of the Lunar New Year?

The sixth day of the first lunar month was the day when all businesses, big and small, would "open for business" in the old days, and a big red couplet with the words "Good luck in opening the business, and everything will go well" would be posted on the door panels. Firecrackers are set off before opening to bring good luck.
Some families find a "completely lovely" woman who has a husband, children, and parents-in-law to go around each house before the market opens on the sixth day of the Lunar New Year, and say auspicious words such as "good luck in the market opening, more than enough blessings, everything will be safe, make more money, and earn enough gold and silver to fill a kang", etc. Before the market opens, it is taboo for women from other families to visit one's home. After the market opens, all Spring Festival taboos will end, everything will return to normal, and neighbors will resume visiting each other immediately.

What is the sixth day of the Lunar New Year called?

The sixth day of the first lunar month is also known as "Horse Day".
Since the Qin and Han Dynasties, the traditional view is that the first day of the first lunar month is the Chicken Day, the second day is the Dog Day, the third day is the Pig Day, the fourth day is the Sheep Day, the fifth day is the Ox Day, the sixth day is the Horse Day, and the seventh day is the Human Day. Legend has it that this is because when Nuwa created all living things, she first created the six domestic animals and then humans, so the first six days of the lunar month are all days for the six domestic animals.
The sixth day of the first lunar month is the Horse Day: go to the fields to prepare for spring ploughing, and send away the poverty.
The sixth day is the Horse Day, known as Yifei in ancient times. People really start working or doing business on this day. Since the beginning of the first lunar month, the toilet cannot be cleaned until the fifth day, and the feces accumulate in the toilet. So on this day, a major cleaning is done to clean the usually dirty toilet. That’s why it’s called “挹肥” (but nowadays most families use new bathroom equipment, so this custom no longer exists). This day also represents the day when the working people in old China began to go to the fields to prepare for spring ploughing.