Taken from Google
If you ask me, there is NONE. Even if it happens once every 100 years, people's lives would improve for the better or for worse depending on how we live it day by day.
But there are couples who will be getting married on this day or babies are born on this day (probably the same sentiments with 1-1-1, 2-2-2, 3-3-3, 1-2-3, 5-6-7, etc).
I hope you enjoy the rest of the day. XD