Is it normal for girls to put on weight between the ages of 16/17 to 20?

When I was around 16, perhaps 17, I was about 4 or 5 kilos lighter (I guess that's about 10 pounds) then I am now (at 20). I like to think that you're kind of becoming a woman and it's normal to get curvier around this age, but I might also subconsciously be making excuses for my weight gain :p
Is it normal for girls to put on weight between the ages of 16/17 to 20?
Post Opinion