Repeating dates of the same sequence or number has become more common since the year 2001, especially since the year can be abbreviated into the last two-digits. The year 2011 holds many interesting dates such as January 1, 2011 (01/01/11 or 1.1.11) where the date can be read the same in both date order formats (MM/DD/YY or DD/MM/YY).

The year 2011 will have many interesting repeating dates such as January 11, 2011 (1.11.11), November 1, 2011 (11.1.11) and November 11, 2011 (1.11.11). These dates only consist of the number one and may cause some confusion when written in its numerical form.

The calendar date can also be read in a repeating sequence such as a sequence of three numbers that are repeated twice or a sequence of four numbers that are repeated twice. For example, in the date order format of MM/DD/YY the date of 10/31/03 consists of a sequence of three numbers (1-0-3) that is repeated twice (103-103).

In the format of DD/MM/YY, the date of October 20, 2010 has an interesting sequence in which the numerical abbreviation is 20/10/2010. This sequence consists of four numbers (2-0-1-0) that are repeated twice (2010-2010). These dates will become more seldom after the year 2013 because the number 13 is not a valid month.