This won't happen again for four years. Will it be a Tuesday? Will it rain that time, maybe? Why does everyone care that it's the 29th? These numbers don't really mean anything. They're just a way for us to tell how long it's been since this, or how long it is until that. The fact that something happened in 1899 doesn't make it any more significant than if it happened in 1901. 11:59pm on December 31 is no different from 12:00am January 1. Eighteen years old is no more significant than twenty-eight years old. The only reason we care is the context that we place and observe.