How Often Does the Calendar Repeat Itself?

Photo Courtesy: AJ_Watt/Getty Images

Many people use calendars to track their day-to-day activities or to plan important events. We rely on calendars to record dates and appointments. We use them to know which years have 365 days or 366. Each year is different when it comes to the days of the week and dates matching up, and without our calenders, we’d likely have a difficult time keeping track of this information.

But did you know that, just because the years are different, it doesn’t mean calendars have never repeated themselves? There are times when the precise sequence of one calendar year repeats in the future. Because of this, it’s possible to reuse calendars, even though you might have to wait a few years. But what calendar do we use, and how often does the calendar repeat? Is this going to happen anytime soon? Let’s find out.

Repeating Calendar Years

Calendars don’t repeat all the time. It isn’t even an annual occurrence, but it has happened more often throughout history than most people probably realize. Essentially, every calendar year has been repeated. For example, looking at 2021, the calendar year is the same as 2010, 1999, 1993, 1982, 1971, 1965, 1954, 1943, 1937, 1926, 1915 and 1909.

Photo Courtesy: JoanDragonfly/Flickr

To continue, 2018 was a repeat of 2007, 2001, 1990, 1979, 1973, 1962, 1951, 1945, 1934, 1923, 1917, 1909 and 1900. The year 2012 (which sparked a discussion about the Mayan “doomsday” calendar) was the same calendar year as 1984, 1956 and 1928. The year 2005 was a repeat of 1994, 1983, 1977, 1966, 1955, 1949, 1938, 1927, 1921, 1910, 1898 and 1887. Finally, the year 2000 was a repeat of 1972, 1944, and 1916.

Even though the calendar years have repeated themselves, there are vast differences in the cultures, trends, politics and technology that were present during these years. The 1930s were much different from the 1990s, and even the 2000s were much different from the 2020s. The calendars might not have changed, but the lifestyles have — making this an interesting study for historians.

What Calendar Do We Use?

If you live in the United States, you use the Gregorian calendar. This is the standard calendar used in most countries across the globe, including Spain, France, Poland, Italy, Germany, Ireland, Greece, Sweden, Egypt, Japan, China and others. You use the Gregorian calendar every day, but you might not even realize how it works or that it has some specific rules and patterns.

ADVERTISEMENT
Photo Courtesy: Bettmann/Getty Images

What Is the Gregorian Calendar?

Before delving into how often the Gregorian calendar repeats itself, it helps to define what this calendar is and how it came to be. Much of the world uses this calendar to specify and record time, specifically days and dates. Like many other calendars, the Gregorian calendar is based on the movements and positioning of the sun. For this reason, it’s known as a solar calendar.

ADVERTISEMENT
ADVERTISEMENT
Photo Courtesy: KAZUHIRO NOGI/AFP via Getty Images

Each year is divided into 12 months, which are then divided into between 28 and 31 days. According to this calendar, we’re currently living in the 21st century, which is also known as the Second Millennium, or the 2000s. However, the Gregorian calendar is not the only calendar, and it’s certainly not the first one people have used in history.

Before the advent of this calendar type, much of Western civilization adhered to the Julian calendar, which was proposed by Julius Caesar and used by the Roman Empire. Before that, different groups used the Roman calendar and the Athenian calendar. Notably, nearly every prominent ancient civilization had its own calendar, and these various calendars didn’t adhere to the same rules.

One of the reasons why the Gregorian calendar has continued to find usage worldwide (despite its 1582 creation and implementation) is that it is a unifying, easy-to-understand concept. It generally keeps the months aligned with each year’s various seasons. However, some cultures and groups around the world don’t recognize the Gregorian calendar or its structure. Instead, they continue to use the calendars their ancestors created. If you’re thinking about reusing a non-Gregorian calendar, it likely won’t be possible. While patterns are commonly found in other types of date-keeping systems, they don’t repeat in the same manner or frequency as they do with the Gregorian calendar.

How Often Does the Gregorian Calendar Repeat Itself?

The Gregorian calendar repeats itself in 28-year cycles. However, some patterns may repeat as few as every six years. Generally, leap years experience the lengthiest pauses between similar day-week patterns (28 years), while non-leap years may repeat every six or 11 years.

ADVERTISEMENT
Photo Courtesy: Archive Photos/Getty Images

During this century, the pattern will hold to an 11-11-6 pattern. This means that a calendar will repeat itself in 11 years. Eleven years after that, it will repeat again. Six years from that date, it will once again become applicable.

For example, take a look at the year 2001. The first day of January 2001 was a Monday. Eleven years prior, in 1990, the new year’s first day had also been a Monday. The same was true of 1979. The next Monday-based New Year’s Day after 2001 came in 2007. Thus, the cycle before 2001 had been 11-11, which left the six-year portion of the cycle to follow, indicating that the next repetition would occur in 2007 (six years later).

Repeating Years to Keep Track Of

While it’s interesting to learn about past calendar years, it’s exciting to have a quick look at upcoming years to know when calendars will repeat themselves. You’ll have a clear understanding of which calendars you can keep and reuse in the near future and which calendars you can recycle.

ADVERTISEMENT
Photo Courtesy: Sina Schuldt/picture alliance via Getty Images

For example, the year 2021 will repeat itself again six years from now in 2027. It will also repeat in 2038, 2049 and 2055. Other repeating calendars in the upcoming future are reusable as follows:

  • A 2022 calendar will repeat in 2033, 2039, 2050 and 2061.
  • A 2023 calendar will repeat in 2034, 2045, 2051 and 2062.
  • A 2024 calendar won’t repeat itself again until 2052.
  • A 2025 calendar will repeat in 2031, 2042, 2053 and 2059.

As calendar years repeat themselves, you save the calendars you love. Maybe you’re sentimental about a personalized calendar, or you like collecting calendars. These calendars will be available to reuse in the future. Keep track of the calendar times, specifically the dates and days of the week, to know when you can reuse the calendars.

To help reuse calendars, try to resist filling in the boxes with notes. This will be a way to reuse calendars without worrying about any future confusion. Reusing calendars can be a fun hobby that allows you to reflect on the past, even if it might take years to reuse them.

ADVERTISEMENT