How heavy should a weighted blanket be?

Body Weight Blanket Weight 50 lbs. 6-7 lbs. 80 lbs. 9-10 lbs. 100 lbs. 11-12 lbs. 120 lbs. 13-14 lbs. 140 lbs. 15-16 lbs. 160 lbs. 17-18 lbs. 180 lbs. 19-20 lbs. 200 lbs. 21-22 lbs.