As you can see, for the past two hundred years human life expectancy has been rising steadily. Soon, most people will live to be over 100 years old. Now, the reason we originally wanted to use two digits is because in our 35-year lifespans (for those of us who love the bacon) we would never be troubled with using the same number twice. Imagine if we called this the year zero, only using the last digit of the year. It would only make sense if we would never live to see the next year zero. But we WILL live to see the next year '10, so we need to act now and change our conventions. In the year '110, it will be too late to go back and change all our blog posts!Act now! Say it with me: Oh-Ten!