Although until 1960s, more than half of the new adults were working youths who had already entered the business world, in and after 1970s, the proportion of students to the total number new adults has been increasing even now due to an increase in the number of people going to university (university advancement rate) and decrease in the number of people finding work after finishing junior high school or high school.
1960年代までは、新成人は半数以上が既に社会に出ている勤労青少年だったが、1970年代以降、大学進学者（進学率）の増加や中卒・高卒就職者の減少から、新成人全体に占める在学者の割合も年々増加しており、現在に至っている。