Managers are determinants of organizational productivity, and their composition is also regarded as a sign of social diversity. However, Japanese managers have not been fully uncovered in terms of their working conditions as well as practices in the workplace. Even government surveys produce inconsistent statistics about managers. For example, while the Population Census by the Ministry of Internal Affairs and Communications shows a downward trend in the proportion of management positions, the Basic Survey on Wage Structure by the Ministry of Health, Labour and Welfare indicates that the share of managers has been constant. In this paper, we summarize the results from an ad hoc survey on 3,000 managers to show that the definition of government surveys may not pertain to a substantial part of managers who are likely to be female and non-standard workers. Since the 1980s, with the extension of non-standard workers in Japanese labor markets, many employers have promoted long-tenured non-standard workers to managerial positions. There is a possibility that government statistics exclude these workers, which may produce downward bias to the proportion of females in managerial positions.