Question on Japan’s taxation of single premium immediate annuities

I have never seen this question addressed in this forum. Assume a Japan tax resident purchases a single premium immediate annuity (SPIA) from a foreign (e.g. US) insurance company and receives a monthly fixed income payments for life. In the US, assuming it is a non-qualified annuity purchased with after tax money, the taxpayer would estimate an exclusion ratio based on life expectancy and expected returns to separate out the share of the annuity payment that is return of capital (already taxed) and income (taxed). Does Japan use the same methodology or would it be somehow different? Anyone with a foreign SPIA have experience with this?

by Few-Asparagus-4140