Tomorrow may not get here so you don't want to keep waiting for some event or some time in order to start going after what you really want.
Your bucket list is composed of things you want to do or want to have. Why should you wait? Do you feel you don't deserve to enjoy those items at this point in life? What will make you worthy to have or pursue them?
Why aren't you worthy now? Do you feel you have an obligation to continue working until you're 'x' years of age? Why? I understand that there are responsibilities people have to fulfill but you don't need to sacrifice everything forever. You read about people who have tragic things happen to them totally unexpected and their lives are changed forever.
In case you think I'm advocating totally shirking all your responsibilities, I'm not. But I'm also not advocating total sacrifice. There has to be some sort of compromise. Make out your list of things you want or want to do and then you can prioritize them by cost or time expenditure or any other characteristic you want. Then start fitting them into your daily activities. Fit them in with your yearly goals. With a bit of creativity you can accomplish some of what's on that special list while continuing your "normal" activities. Creativity will add life to your existence as well.
Think about it. Try to find ways to enjoy everything NOW. Live in the now and you will be fulfilled. Be grateful for everything you have and the more gratitude you feel and express, the more you will receive back.
Start your wish list (a better word than bucket list) now and see how you can start incorporating the things in your life now -don't even wait for the new year to start. Tomorrow never comes. Make great use of today!