An estimated 6.24 million people in Japan aged 65 or older were living alone in 2015, exceeding the 6 million mark for the first time, according to a welfare ministry survey released Tuesday that also showed economic distress felt by many of the elderly.

There were 12.71 million households comprised of mainly those seniors and couples in the age bracket, up 500,000 from the previous year, and they comprised 25.2 percent of all households in the country.

Among the households comprised of seniors, 58.0 percent reported difficulties making a living, according to the survey.

The survey pointed to hardships experienced by many seniors, with 55.0 percent of the households that received public pensions or other benefits saying they had no other source of income.

The survey had a bit of good news for a country suffering from a chronically low birthrate. The number of households with at least one child under 18 increased to 11.82 million, from 11.41 million in 2014, apparently due to a rise in the fertility rate.

But 63.5 percent of such households reported economic hardships, even though in 2014 the average household income rose for the first time in three years to ¥5.42 million ($52,250), according to the survey.

A record 68.1 percent of households with at least one child under 18 had working mothers in 2015.

Men with nonpermanent jobs accounted for 16.0 percent of all working men, while women with such jobs comprised 46.1 percent of all working women.

The survey was conducted in June and July of last year. Overall numbers were estimated from valid responses obtained from about 46,000 households with regard to household affairs and from about 6,700 households over income information.