Japanese bonds – yielding close enough to zero – have been a fantastic investment for about twenty years.
After all seven year JGBs were yielding above 1 when I was (unfortunately) short them. Nominal prices were dropping more than three percent per year.
So the return on owning JGBs was over 4 percent real per year. Tax only applied to the nominal part of the return – so the post tax return was about 4 percent per year REAL.
Now how long did you need to hold stocks to get a 4 percent post-tax real return?
Mrs Watanabe with her large JGB holding has seemingly done OK.