Last summer the welfare ministry reported that a record number of households were receiving government assistance, and 47.1 percent of these households were made up of either elderly people only or the elderly and unmarried family members under 18. The media has been reporting for years that an increasing number of seniors are joining the welfare rolls. National pensions were never meant to cover every retiree's living expenses, but it's obvious that many are not prepared for their old age.

How much do you need to save in order to guarantee a comfortable life when you retire? The anonymous 30-year-old who writes the popular investment blog Setsuyaku Toshi no Susume recently wondered the same thing when he realized his parents would be broke by the time they retired. He will support them in their old age, but he doesn't want to be a "burden on my own children."

He cites a 2013 survey by the Japan Institute of Life Insurance, who questioned more than 4,000 married couples about their retirement plans. One-third of the respondents said they needed "at least" between ¥200,000 and ¥250,000, and another third answered between ¥250,000 and ¥400,000. Only 5 percent thought they could make it on less than ¥150,000, and 1.7 percent couldn't do with less than ¥400,000. The average for all responses was ¥220,000.