I'm going to propose to my girlfriend, but what is the best and luckiest date to do so?

I want to make sure I am on the best chance of her saying yes. What would be the best date and year to propose to my girlfriend? Her birthday is December 23 1993. Mine was on August 26 1996. I know we will have our fights and all, but I really love this girl, and I need to know. Please help me out.