The guide below is of use both to new collectors and those with sets from previous years.
Collectors who wish to start collecting with the current year please note that 2009 will be useable in just six years in 2015. Similarly, 2013 will be reusable six years later in 2019. And so forth. (The six year formula doesn't always apply because of leap years, however. See below.)
Guide to Reusing Calendars For the Next 15 Years
2009 1981, 1987, 1998, 2015
2010 1982, 1993, 1999, 2021
2011 1977, 1983, 1994, 2005
2012 (leap) 1984; or combine 1989 Jan-Feb (accept missing Leap Day in Feb)
and 1990 Mar-Dec
2013 1985, 1991, 2002, 2019
2013 1985, 1991, 2002, 2019
2014 1975, 1986, 1997, 2003
2015 1981, 1998, 2009 2016 (leap) 1988; or combine 1982, 1993, 1999, 2010 Jan-Feb (accept missing Leap Day in Feb) and 1977, 1983, 1988, 1994, 2005 Mar-Dec
2017 1989, 1995, 2006, 2023
2018 1979, 1990, 2001, 2007
2019 1985, 1991, 2002, 2013 2020 (leap) 1992; or combine 1986, 1997, 2003 Jan-Feb (accept missing
Leap Day in Feb) and 1981, 1987, 1992, 1998, 2009, 2015 Mar-
Dec
2021 1982, 1993, 1999, 2010
2022 1977, 1983, 1994, 2005, 2011 2023 1978, 1989, 1995, 2006, 2017
2024 (leap) 1996; or combine 1979, 1990, 1996, 2001, 2007, 2018 Jan-Feb
(accept missing Leap Day in Feb) and 1985, 1991, 1996, 2002,
2013, 2019
The Leap Year Problem and Solution
Every four years a 'leap year' occurs which adds an extra day to February, the date of February 29th, which is also known as Leap Day. (Leap years occur on the same cycle as presidential election years.)
Sometimes past leap year calendars will be reusable in future leap years, but that's relatively rare.
For Collections Including a Number of Past Years By the Same Artist
For collectors who own a number of sets by the same artist from previous years, there is a simple solution to the leap year problem. Combine sets from different years and ignore the Leap Day. That is, use January and February from one year and March through December from another year, and accept the fact that February 29th will be missing from the calendar set. Note however that this solution really only works for folks with fairly large collections of the same artist.
For Smaller Collections Including Mostly Recent Years
Buy a brand new calendar set for the leap year in question. Or design your own!
