Lifetime employment and seniority-based wages are balanced by a very early mandatory retirement age. It has been customary for private firms as well as the government to retire regular male employees at ages ranging from 55 to 62. Earlier retirement ages for women were common until the Supreme Court declared the practice to be discriminatory and illegal. As regular employees these retirees receive some form of pension, either as a large lump sum severance payment or as a regular monthly pension. These relatively young retirees generally continue working for several more years on a contract or part time basis, sometimes for the same employer or for an affiliated firm. They no longer earn a seniority-based wage, and they no longer enjoy long-term job security in these post-retirement positions. The Japanese government has a modest old age pension system that is similar to the American Social Security system.