Last time, I compared the implications of tax incentives for freshly-picked NISA and iDeCo. In particular, iDeCo's full income deduction, which anyone can say is "always profitable," is a merit that NISA does not have. But not everyone chooses iDeCo. Isn't the difference in tax incentives the decisive factor in choosing a system? This time, let's dig a little deeper into the comparison of tax systems.