It is clear that there are a lot of opinions about the appropriate retirement age and many countries have different standards about it. However, I firmly believe that 60 is the most appropriate age.
Prior to saying my opinion, some people claim that the retirement age should be prolonged by 70. Because a life expectancy is extended and they have to work longer to earn the money. Furthermore, there are lots of advantages when we work with old people. For instance, we can solve some problem easily by receiving advice from them. They experienced various kinds of problem and already know how to solve it and prevent it. We can learn the know-how from them.
Meanwhile, they may reduce the opportunities for young people to get the job since they hold job consistently and companies are not able to hire more employees. Moreover, the salary of them is much higher than one of a newcomer. In my country, some study said that making old people who have worked for a long time and receive a high wage work less helps a company to hire newcomers. And it can solve the unemployment crisis.
The life expectancy has been extended, but it doesn’t mean that people have to work longer. If we resign from a company early, we can try to another area which we have not experienced. For example, the friend of my father's retired when he was 55 and it was a much earlier age than others. Most friends of his concerned that he lost his job. Nevertheless, he has enjoyed his new hobby, which is researching cuisines and recording them in his cookbook.
For these reasons, I think it is appropriate for people to retire when they are 60. In my opinion, it is the proper time for them to finish their duty to take care of their children. And it is enough for them to try something new.