Milestone reached

So the big day for the big 3-0 came and went without a hitch or a worry. I had a most awesome day, thanks in particular to my wonderful girlfriend who made the day complete. But other than a number, what is the particular importance of decade birthdays? Why do they seem more important than any other birthday, or even just a regular day for that matter?

I didn't freak out, or run out and buy a red convertible...it was just another day for me. I took the day off because I could, and just sat at home and relaxed ALL DAY until it was time to pick my girlfriend up and go to dinner. We went to Topolobampo in downtown Chicago. If you've never been there, I'd highly recommend this restaurant (more than the sister/adjoining restaurant, Frontera Grill). Topolo is upscale Mexican cuisine, and I can begin to describe how wonderful the food is. It is a bit on the pricey side, but well worth the extra for a nice dining experience.

Anyway, events aside, who set 30, 40, 50 year birthdays as "milestones" anyway? What's the significance? If you're celebrating every decade, why not ever 5 years as well as being a big milestone? I know, stupid thought, but after the big deal everyone around me threw about being 30, I was just wondering...

Cheers,
Rocco