Photo/Illutration A news conference held by UA Zensen on Dec. 12 (Junpei Miura)

About 40 percent of married women who are working part time take measures to ensure their annual incomes do not exceed the “1.03 million yen ($7,600) wall,” the standard for a spouse tax credit, a survey showed.

The spouse tax credit is provided for the income tax payments of people whose spouses have lower annual incomes. But the spouse’s annual income cannot exceed 1.03 million yen for the tax credit.

If the income tops that standard, the spouses are not considered dependents and their marriage partners cannot receive the deductions.

The survey was conducted by UA Zensen, one of the largest industrial unions in Japan, from January to April on 8,731 members whose husbands were full-time employees.

According to the results released on Dec. 12, 36.7 percent of the women said they took days off to lower their annual incomes and avoid increases in their husbands’ income tax payments.

“Because of the annual income wall, it appears that they are trying to reduce their working hours,” a representative of the union said.

The system has also created a manpower shortage and needs to be reviewed, the representative said.