Thats definitely not normal. However, for my family, that is VERY normal
For 2011, For four of us, around $20,000 NOT including premiums. This is more than 20% of my dads take home pay. This includes our deductable, OOP max, copays, medications, psychotherapy and dental.
For 2010, it was about $15,000....in the past 9 years, we have spent more than $100,000 OOP NOT including premiums. Basically my entire college education plus some.
We have whats considered a "premium" plan insurance through my dads work. $750 dedcutable, $8000 OOP max (family), 90/10 coinsurance. Our copays are still $20/$40. I have 3 doctors who are considered primary ($20) and 5 considered speacialists ($40). I probably average about 6-7 appts/month (of course mostly specialists). Plus my parents copays and my brothers.
This past year, so for 2011, I alone had about $190,000 in medical claims.
So I would say that $18,000 is not even close to normal for the average family. It's not far fetched though for families with medical conditions though. This is why about 70% of the individuals who have claimed bankruptcy because of medical bills are individuals who HAVE insurance.