Around 50% on lvl 2
Feels bad man
Assuming you're level 2; You get 50 experience per day by making replies, and if we do the math: 500/50 = 10
It would take you 10 days to get to level 3.
Very important to be consistant!
Every day you write something, you get one day closer.
Its ~4% per article comment or half that for forums, so ~25 article comments or ~50 forum coments should do it, but there also appears to be a cap per day around 150xp