This paper proposes to take the age at which a scientist achieved his first success as his famous-becoming age; uses a statistical method to obtaine the optimum age of scientists for making scientific discoveries; uses the same to find the experiential formula that explains the relationship between the number of scientific achievement and the number of scientists and their ages. Employing this formula, it expounds to some extent the Yuasa Phenomenon. For conclusion it analyzes the scientific value of experiential formula and the reliability of its scope of prediction.