Please, please, please don't EVER use BMI. Use your straight body fat percentage. BMI makes absolutely no accounting for muscle. Virtually every professional athlete in the world would be considered obese based on BMI because it is strictly height v. weight.
For example, I was a high school and college athlete. At 22 and at 20% body fat (low for a woman), I went in for my yearly exam with a new doctor. Without looking at me, the doctor reviewed my chart, saw my height and weight, referenced the BMI chart and told me I should lose 20 lbs. At 20% body fat. Needless to say, I reamed him a new one and explained how these types of ridiculous comments lead to eating disorders in young women. BMI is outdated and wholly inaccurate.
"If you won't be better tomorrow than you are today, what do you need tomorrow for?"