calculates. I was just playing around on a BMI calculator. It says that for me, 6'0", 137 lbs is the low end of a normal body weight. 180 is the start of being overweight.
137lbs at 6'0" is anorexic and sickly looking. 180lbs at 6'0" is very average. There is way more data needed than just calculating BMI off of height and weight.
But either way, congrats. lowering your BMI by 8 points is a major accomplishment.