A record 38.7 percent of private-sector workers in their 20s to 50s said their household finances fell into the red during the past year, a research institute said Thursday.

"While the economy is recovering slightly, many workers still have a negative view of their employment and wage conditions," the Research Institute for Advancement of Living Standards said, based on a survey earlier this month, to which 573 workers in the Tokyo and Osaka areas responded.

Among respondents with an annual income of less than ¥4 million, 60.4 percent said their household finances went into the red, with the figure climbing to 62.9 percent among male irregular employees, according to the think tank of the Japanese Trade Union Confederation, known as Rengo.

Of particular note were the 31.4 percent of male nonregular employees who said they could not pay taxes and social insurance premiums and the 20 percent who cut back on food.

The survey also found that 17.1 percent of such workers couldn't afford to see doctors because of their financial difficulties.