The fourth fiscal estimate of the national pension following the aging of the population and falling yields estimated that the fund ran out in 2057, three years earlier than the third fiscal calculation. Accordingly, the government proposed a plan to immediately raise the insurance premium rate by 2 percent and maintain the income replacement rate by 45 percent, and to reduce the income replacement rate by 40 percent in 2028. In this form, increasing premiums and reducing income replacement rates will allow younger generations to sign up differently from existing subscribers, who previously had higher income replacement rates at lower rates. Therefore, the study aims to ease the burden on the elderly and younger by applying different insurance rates and income replacement rates for different ages.