Nenshuu-no-Kabe (the ceiling of annual earnings)

Nenshuu-no-Kabe (the barrier of annual earnings) is discussed based on the employment Income (a family of employee, his wife, and children) mainly.

①Employment income

②a part-time income from his wife and children

③total income =①＋②

In case of each income (①/and/or ②) which is exceeding of ceiling of income, they may have an increase of income tax, residential tax and/or social insurance fee.

This means total family cash flow is decreasing. This is why a people does not want to work exceeding the ceiling of amount of income.