The Binding of the Years occurred every 52 years, or every 18,980 days as a part of the combination of the two calendars. Arithmetically, the duration of the Calendar Round is the least common multiple of 260 and 365; 18,980 is 73 × 260 Tzolkʼin days and 52 × 365 Haabʼ days derived from the Maya calendar.
Every 52 years or every 18,980 days, as part of two calendars, the Binding of the Years occurred. In terms of mathematics, the Calendar Round's duration is the least common multiple of 260 and 365; 18,980 represents 73 times 260 Tzolkʼin days and 52 times 365 Haabʼ days from the Maya calendar.