The whitepaper actually says that 28% of Japan is over 65.
Maybe 75% is a misunderstanding of the "Old-age dependency ratios 1950-2050 in the 19 countries of study" chart. That shows that in 2050 Japan will have 74.32 people over 65 for every 100 people between 15-64.
Maybe 75% is a misunderstanding of the "Old-age dependency ratios 1950-2050 in the 19 countries of study" chart. That shows that in 2050 Japan will have 74.32 people over 65 for every 100 people between 15-64.