The so-called developmental quotient refers to the ratio of the baby’s five major abilities to the norm. The normal value is 90 to 115, accounting for about 75% of the population. 116 to 129 are relatively smart, and those over 130 are considered supernormal and become supernormal children. Those between 70 and 89 are relatively lagging behind, and those below 69 are mentally retarded. One year of early development training for infants and young children can generally improve their performance by 20 percentage points compared to the natural state.