The change between 16 and now would definitely be the most drastic... but I imagine that would be the same for most people. I'm 80 pounds (36 kg) lighter now than I was at my heaviest, which was sometime between 16 and 19? I think it was closer to 19, because that's when I had major surgery and dropped like 20 pounds in a week. Side effect of not eating anything with a body desperately trying to heal itself.
I'm down 40 pounds from December, though, which was still one of my lighter phases.
I'm also balder now than I was at 16, though. :(