A Decomposition of Life Expectancy and Life Disparity: Comparison Between Hong Kong and Japan

Document Type : Original Article


1 Department of Social Work and Social Administration, Faculty of Social Sciences, The University of Hong Kong, Hong Kong, China

2 Center for Demographic Research, Université catholique de Louvain, Ottignies-Louvainla-Neuve, Belgium

3 HKJC Centre for Suicide Research and Prevention, The University of Hong Kong, Hong Kong, China


Life expectancy and life disparity are 2 useful indicators to assess the health condition of a society. Both Hong Kong and Japan have one of the longest life expectancies in the world. Recently, Hong Kong has overtaken Japan and topped the life expectancy rankings. However, whether Hong Kong has also outperformed Japan in life disparity is still unknown.

Decomposition analyses have been conducted to evaluate age-specific contributions to the changes in life expectancy and life disparity for each of the populations. Furthermore, the differences between the 2 populations were examined over the period 1977-2016.

Reduction in mortality of the adult and the old age groups contributes most to the increase in life expectancy for the study period. Hong Kong has a higher life disparity than Japan, and due to the great improvement in reducing premature deaths, the Hong Kong-Japan gap has been narrowing. However, in recent years, further reduction in mortality of the oldest elderly in Hong Kong has actually contributed to the increase in its disparity, thus widening its gap with Japan again.

Increasing dominant influence of “saving lives at late ages” is very likely to cause the reemergence of increasing life disparity in these 2 long-lived populations.


Supplementary File 1 (Download)


  1. Smits J, Monden C. Length of life inequality around the globe. Soc Sci Med. 2009;68(6):1114-1123. doi:10.1016/j.socscimed.2008.12.034
  2. Hiam L, Harrison D, McKee M, Dorling D. Why is life expectancy in England and Wales 'stalling'? J Epidemiol Community Health. 2018;72(5):404-408. doi:10.1136/jech-2017-210401
  3. Tuljapurkar S. The final inequality: variance in age at death. In: Shoven JB, ed. Demography and the Economy. University of Chicago Press; 2010.
  4. Edwards RD, Tuljapurkar S. Inequality in life spans and a new perspective on mortality convergence across industrialized countries. Popul Dev Rev. 2005;31(4):645-674. doi:10.1111/j.1728-4457.2005.00092.x
  5. Wilmoth JR, Horiuchi S. Rectangularization revisited: variability of age at death within human populations. Demography. 1999;36(4):475-495. doi:10.2307/2648085
  6. Shkolnikov VM, Andreev EM, Begun A. Gini coefficient as a life table function: computation from discrete data, decomposition of differences and empirical examples. Demogr Res. 2003;8:305-358. doi:10.4054/DemRes.2003.8.11
  7. Vaupel JW, Zhang Z, van Raalte AA. Life expectancy and disparity: an international comparison of life table data. BMJ Open. 2011;1(1):e000128. doi:10.1136/bmjopen-2011-000128
  8. Vaupel JW, Romo VC. Decomposing change in life expectancy: a bouquet of formulas in honor of Nathan Keyfitz’s 90th birthday. Demography. 2003;40(2):201-216. doi:10.1353/dem.2003.0018
  9. Zhang Z, Vaupel JW. The age separating early deaths from late deaths. Demogr Res. 2009;20:721-730. doi:10.4054/DemRes.2009.20.29
  10. Census and Statistics Department, The Government of the Hong Kong Special Administrative Region website. https://www.censtatd.gov.hk/home/index.jsp.  Accessed May 1, 2019.
  11. Cheung KS, Yip PS. Trends in healthy life expectancy in Hong Kong SAR 1996-2008. Eur J Ageing. 2010;7(4):257-269. doi:10.1007/s10433-010-0171-3
  12. Law CK, Yip PS. Healthy life expectancy in Hong Kong special administrative region of China. Bull World Health Organ. 2003;81(1):43-47.
  13. Yu R, Leung J, Lum CM, et al. A comparison of health expectancies over 10 years: implications for elderly service needs in Hong Kong. Int J Public Health. 2019;64(5):731-742. doi:10.1007/s00038-019-01240-1
  14. Zheng Y, Chang Q, Yip PSF. Understanding the Increase in Life Expectancy in Hong Kong: Contributions of Changes in Age- and Cause-Specific Mortality. Int J Environ Res Public Health. 2019;16(11). doi:10.3390/ijerph16111959
  15. Chen M. Ultra-low fertility in high-income Asian societies: a comparison of Hong Kong, Taiwan, Singapore, South Korea, and Japan [thesis]. Hong Kong: University of Hong Kong; 2017.
  16. Boccardi V. Population Ageing: The Need for a Care Revolution in a World 2.0. Geriatrics (Basel). 2019;4(3). doi:10.3390/geriatrics4030047
  17. Human Mortality Database. University of California, Berkeley (USA), and Max Planck Institute for Demographic Research (Germany). https://www.mortality.org.  Accessed December 1, 2018.
  18. Németh L. Life expectancy versus lifespan inequality: a smudge or a clear relationship? PLoS One. 2017;12(9):e0185702. doi:10.1371/journal.pone.0185702
  19. Wilmoth JR, Andreev KF, Jdanov DA, et al. Methods protocol for the human mortality database. University of California, Berkeley, and Max Planck Institute for Demographic Research, Rostock; 2019. https://www.mortality.org [version 5/10/2019].
  20. Singh A, Ladusingh L. Life expectancy at birth and life disparity: an assessment of sex differentials in mortality in India. Int J Popul Stud. 2016;2(1):38-52. doi:10.18063/IJPS.2016.01.005
  21. Aburto JM, van Raalte A. Lifespan dispersion in times of life expectancy fluctuation: the case of Central and Eastern Europe. Demography. 2018;55(6):2071-2096. doi:10.1007/s13524-018-0729-9
  22. Shkolnikov VM, Andreev EM. Age-decomposition of a difference between two populations for any life-table quantity in Excel. Rostock: Max Planck Institute for Demographic Research; 2010.
  23. Yanagishita M, Guralnik JM. Changing mortality patterns that led life expectancy in Japan to surpass Sweden’s: 1972–1982. Demography. 1988;25(4):611-624. doi:10.2307/2061325
  24. Shkolnikov VM, Andreev EM, Zhang Z, Oeppen J, Vaupel JW. Losses of expected lifetime in the United States and other developed countries: methods and empirical analyses. Demography. 2011;48(1):211-239. doi:10.1007/s13524-011-0015-6
  25. Seaman R, Leyland AH, Popham F. Increasing inequality in age of death at shared levels of life expectancy: a comparative study of Scotland and England and Wales. SSM Popul Health. 2016;2:724-731. doi:10.1016/j.ssmph.2016.10.001
  26. van Raalte AA, Sasson I, Martikainen P. The case for monitoring life-span inequality. Science. 2018;362(6418):1002-1004. doi:10.1126/science.aau5811
  27. Brønnum-Hansen H. Socially disparate trends in lifespan variation: a trend study on income and mortality based on nationwide Danish register data. BMJ Open. 2017;7(5):e014489. doi:10.1136/bmjopen-2016-014489
  28. van Raalte AA, Martikainen P, Myrskyla M. Lifespan variation by occupational class: compression or stagnation over time? Demography. 2014;51(1):73-95. doi:10.1007/s13524-013-0253-x
  29. Seligman B, Greenberg G, Tuljapurkar S. Equity and length of lifespan are not the same. Proc Natl Acad Sci U S A. 2016;113(30):8420-8423. doi:10.1073/pnas.1601112113
  30. Yip PS, Chen M. What really matters: living longer or living healthier Comment on "Shanghai rising: health improvements as measured by avoidable mortality since 2000." Int J Health Policy Manag. 2015;4(7):487-489. doi:10.15171/ijhpm.2015.87
  31. Basten S, Yip P, Chui E. Remeasuring ageing in Hong Kong SAR; or ‘keeping the demographic window open.’ J Popul Res. 2013;30(3):249-264. doi:10.1007/s12546-013-9113-1
  32. Yip PSF, Cheung KSL, Law SCK, Chi I, Robine JM. The demographic window and economic dependency ratio in the Hong Kong SAR. Asian Popul Stud. 2010;6(2):241-260. doi:10.1080/17441730.2010.494452
  33. van Raalte AA, Kunst AE, Deboosere P, et al. More variation in lifespan in lower educated groups: evidence from 10 European countries. Int J Epidemiol. 2011;40(6):1703-1714. doi:10.1093/ije/dyr146
Volume 10, Issue 1
January 2021
Pages 5-13
  • Receive Date: 18 March 2019
  • Revise Date: 07 December 2019
  • Accept Date: 14 December 2019
  • First Publish Date: 01 January 2021