Don't get your panties in a bunch trying to count, it's easy to figure out.
1st: Search for post by your username, in accending order
2nd: Get the date from your 1st result (top corner of box)
3rd: Go here and paste the date from step 2 in the first part, and the current date (12.2.06) in the second part.
4th: Calculate, Copy, and Paste
I've been here 489 days, woo!