Adolescents should always talk to their doctors before embarking on a weight loss diet.  A 60 pound loss over 52 weeks seems reasonable, but it may interfere with some phase of your growth.  I prefer to see you eat 1850 calories a day, the number it takes to maintain your goal weight (128 lbs or BMI 22) at a light activity level. That way, you would lose 35 pounds in one year and the rest in year two.  The “diet” would have no end because you’d be eating your maintenance calorie requirements, and it would force you to increase your activity level from 'sedentary' to 'light', which is necessary to maintain weight loss.