Applying Fertility Projection System to Period Effect Analysis:

1. Joint Eurostat-UNECE Work Session on Demographic Projections April 28-30, 2010, Lisbon An Examination on Recent Upturn in Japan Applying Fertility Projection System to Period Effect Analysis: Ryuichi Kaneko National Institute of Population and Social Security Research Tokyo, Japan

2. Three Objectives (1) To show the usefulness of population projection in analyzing past and current demographic processes. (2) To classify and clarify the period effects in terms of changes in cohort fertility schedule. (3) To see the cause of the recent fertility upturn in Japan. Is it same as Euro & US?

3. Period Effect Term “Period Effect”came from epidemiology,specifically from APC-Analysis,denotes changes caused by period phenomena. Demographer needs another definition,because the Temp-effect is one of period effects, but is caused by cohort changesin age distribution of the event.

4. Period Effectof Fertility Period effect can’t be defined in terms of causes.We usually don’t know the causes of fertility changes. Causes are for us to be identified. Tentative Definition :Period Effect is a change in fertility rate in a certain period, which does not influence the completed fertility of participating cohorts.

5. Types of Period Effectin Fertility

6. Figure3 Types of Period Effect in Terms of Cohort Fertility Schedule (1) (2) Type-Tl Type-Td (3) (4) Type-H Type-Ts

7. Period Effectof Fertility Period Effect of type-T isinduced by three types of timing shiftin cohort fertility schedule. type-Tl : location shift type-Td : dispersion shift type-Ts : shape shift Period Effect of type-H is transient and unpredictable. incorporated in cohort fertility projections can not be in population projections

8. Figure3 Types of Period Effect in Terms of Cohort Fertility Schedule (1) (2) Type-Tl Type-Td (3) (4) Type-H Type-Ts

9. A Case Example of Type-H Period Effect: The Hinoe-uma Effect in 1966 in Japan Hinoe-uma

10. Figure 4 ASFR of Japanese Female Cohort Born in 1935: An Example of PE(type-H) born in 1935 Hinoe-uma (Fiery Horse)

11. Figure 4 ASFR of Japanese Female CohortsAn Example of PE(type-H) born in 1932 born in 1935 H H H born in 1938 born in 1941 H

12. Figure3 Types of Period Effect in Terms of Cohort Fertility Schedule (1) (2) Type-Tl Type-Td (3) (4) Type-H Type-Ts

13. Why is the distinctionbetween type-T and type-Himportant?

14. Trends of Total Fertility Rate in Japan type-T period effect ? (recuperation?) or type-H period effect ? (boom?)

15. How to Detect and measure the Period Effect of type-H

16. Figure 10 Actual and Modeled Cohort Fertility Rates by Birth Order by Five Year Age Groups ●Actual --- Model

17. Period TFR: Actual and Projection Model Detection of Period Effect of type-H Figure 5 Trends of Total Fertility Rate: Observed and Assumed

18. Results :the Period Effect of type-Hin Recent JapaneseFertility Trend

19. Figure11 Estimates of Type-H Period Effects -Differences between Actual and Projected Fertility Rates- by Five Year Age Groups by Birth Order

20. Some Other Analyseson the Fertility Upturn in 2006-8 in Japan

21. Figure6 Monthly Progresses of Fertility Rates by Birth Order: 2002-2009 (1) (2) (3) (4) (1) (2) (3) (4) (1) (2) (3) (4) (1) (2) (3) (4)

22. Figure9 Trends of the Total Fertility Rates with/without Tempo-adjustment

23. Figure4 Type-H’ is Not a Genuine Period Effect, But it Starts Similarly Type-H Type-H’ Type-H’ is not a genuine period effect, because it changes cohort completed fertility. It rather be classified a period-cohort effect.

24. Conclusion (1) • The recent upturn could mainly be explained by the period effect, which would not change cohort completed fertility, and particularly the effects that temporally works and would be redeemed in other period ( the type-H period effect ).

25. Conclusion (2) • The upturn seems to be caused by a rebound of the short term too-low fertility in preceding period, followed by a boom among singles and under-parity families. • These are the different in causes from the upturns seen in the US and Europe with so-called "the tempo transition. “(type-T period effect in our terminology)

26. Conclusion (3) • However, if boom continues for long enough to raise the levels of completed fertility (type-H‘ effect), the long term prospect should be higher than the presently assumed. • The proposed method seems work well for the past trends to detect type-H period effects. But it may not be reliable for the current trend to the extent that predicted cohort fertility may be unreliable.

27. Conclusion (4) • Period Effect The period effects should be classified and clarified in terms of cohort fertility schedule shift so that type of period can be sorted and separated. • Projection Techniques for AnalysesModels of population projection can play a significant role in analyzing past and current demographic processes as well as forecasting its future course.

28. Thank you …

30. Table 1 Contribution of Subgroups to Period Effects of Type H in Selected Years by Five Year Age Groups by Birth Order Note: Comparatively outstanding values for the age groups and birth order are underlined.

31. Figure8 Monthly Progresses of the Mean Age at Birth by Birth Order: 2002-2009

32. Figure5 Trends of Total Fertility Rate: Observed and Assumed

33. Figure 11 Estimates of Type-H Period Effects -Differences between Actual and Projected Fertility Rates- By Age and Year Age Age Year Year