The average annual increase in the number of myopia in adolescents is also dependent on age, generally at the age of 6-7 years old or before 12 years old belongs to the peak growth stage, myopia may grow relatively fast, the average year may be in the 75-100 degrees. If you go to high school, that is, after the age of 13-14, this process may be relatively myopia growth will be relatively less, on average, a year is in the 50-75 degrees or so. However, although there is a difference between these two stages, the annual increase in the number of degrees is relatively large. If a child of 6-7 years old starts with more than 100 degrees of myopia, after 18 years of age, he or she may have about 800-900 degrees of myopia. Therefore, the prevention of myopia should start at an early age, and if myopia is found to be growing relatively quickly, more than 75-100 degrees per year, you need to take certain measures to prevent and control it, such as wearing ok lenses or using low concentration atropine drops, both of which can effectively slow down the growth of myopia.