DOY

They say don't count the days, make the days count. Why not do both?
40 years ago, when I was serving in the U.S. Army Field Artillery, the PX sold tapes with tear-away numbers, allowing 'short timers' to countdown the days as they neared the end of their active duty service. Those tapes are the inspiration for DOY, which tracks the number of days until a user configurable set of events.
As a bonus, for each upcoming event, DOY also provides the Day Of Year, and sunrise and sunset times based on your current longitude and latitude.