1. 1) Ministry of Health, Labour and Welfare. Abridged life tables for Japan 2017. (accessed 2018 Nov 13) Available from:https://www.mhlw.go.jp/english/database/db-hw/lifetb17/dl/lifetb17-05.pdf
2. 2) National Institute of Population and Social Security Research. Population projections for Japan: 2016-2065 (with long-range population projections: 2066-2115). 2017. (Population research series
3. 336). (accessed 2018 Nov 13) Available from: http://www.ipss.go.jp/pp-zenkoku/j/zenkoku2017/pp29_ReportALL.pdf
4. 3) Hashimoto R. Kenkoujumyou no zenkokusuii no santei/hyoka ni kansuru kenkyu. (accessed 2018 Nov 19) Available from: http://toukei.umin.jp/kenkoujyumyou/houkoku/H29.pdf
5. 4) Ministry of Health, Labour and Welfare. Summary report of comprehensive survey of living conditions 2016. (accessed 2018 Nov 19) Available from: https://www.mhlw.go.jp/english/database/db-hss/dl/report_gaikyo_2016.pdf