Chinese social media has reacted with amusement — and some confusion — to the news that one of the nation’s most important holidays will technically disappear from the calendar for five years starting from 2025.

Chinese New Year’s Eve is one of the highlights of the Spring Festival holiday, when families across the country reunite to share a lavish meal and ring in the new year by setting off fireworks, exchanging gifts, and hanging red banners decorated with rhyming couplets.

The festivities normally take place on the 30th day of the 12th lunar month — known as danian sanshi in Chinese — in China’s traditional calendar. But a quirk in the lunisolar cycle means the day is set to be skipped for the next half-decade.

Like every calendar, the traditional Chinese calendar does not match up exactly with the movements of the Sun and Moon, meaning that some adjustments have to be made occasionally to correct for these small discrepancies.

In the Gregorian calendar, which is based on the solar cycle, this is done by adding an extra day in February once every fourth year — known as a Leap Year. But the Chinese system is mostly based on the lunar cycle and has a different method.

The length of the lunar month fluctuates slightly throughout the year, ranging from 29.27 days to 29.82 days. The Chinese system corrects for these changes by dividing the calendar into “big months” lasting 30 days and “little months” lasting 29 days.

If the last month of the year happens to be a “little month,” then the 30th day will be skipped over, meaning that danian sanshi will disappear from the calendar that year.

Though it is far from unusual for danian sanshi to be skipped over in a given year, experts told the state-run Xinhua News Agency that it is “relatively rare” for this to happen five years in a row.

The news has attracted significant interest on Chinese social media in recent days, with a related hashtag receiving more than 12 million views on the microblogging platform Weibo.

The reaction has mostly been one of amusement. One commenter jokingly blamed the Moon for the change, writing: “It’s all the Moon’s fault.” Another lamented that as they were born on the 30th day of the 12th lunar month, they wouldn’t have another birthday until 2030.

There were also some worries that the public holiday for Chinese New Year’s Eve might disappear in years without a danian sanshi. But officials have reassured the public that this is not the case, as Chinese New Year’s Eve will simply be celebrated on the 29th day of the 12th lunar month instead.

The Chinese government recently announced that starting from next year the country will grant an extra day of public holiday for Chinese New’s Year Eve, meaning that the 2025 Spring Festival holiday will last eight days — from Jan. 28 (the 29th day of the 12th lunar month) to Feb. 4 (the 7th day of the first lunar month).

The change is designed to encourage consumption on Chinese New Year’s Eve, which is not only an important traditional holiday, but also a massive commercial event in China.

The run-up to the holiday sees an enormous spike in travel each year, as hundreds of millions of people return to their hometowns to visit their relatives — or, increasingly, jet off on vacation.

The Spring Festival is also a make-or-break period for businesses across a swathe of industries — from food companies to film studios — while state broadcaster CCTV’s Spring Festival Gala on Chinese New Year’s Eve is the world’s most-watched TV program, attracting around 1 billion viewers each year.

(Header image: VCG)