Children between the ages of 2 and prepubertal can be calculated using the formula for normal height: number of years x 7 + 70 (cm). Below the normal height of 2 standard deviations (about 6-7% of the normal height), or height is lower than the average height of children of the same age and sex 3 percentile in layman’s terms. It is a hundred children of the same age and sex in line according to the size, the last three are short is called short stature.