TL;DR: Evidence suggests that beliefs about good and bad years according to the zodiac have changed birth numbers in some East Asian countries and in Vietnam. In Vietnam, a study by Do and Phung (2010) found that birth cohorts in years considered good were about 12% larger; among ethnic Chinese in Singapore, Malaysia, Taiwan, and Hồng Kông, births rose in Dragon years and fell in Tiger years. Goodkind's (1995) study of ethnic Chinese in Malaysia further showed that districts with lower Chinese proportions saw more widespread Dragon year timing, and Vere (2008) showed that zodiac-driven birth fluctuations are strong enough to use as a natural experiment. This is evidence of behavior influenced by belief, not evidence that the zodiac determines human destiny.
Does the Year of the Dragon Really Increase the Number of Births?
Yes, in some countries and Chinese communities, the number of births rises in the Year of the Dragon and falls in the Year of the Tiger. In Vietnam, the evidence comes mainly from a study by Quy-Toan Do and Tung D. Phung (2010), which shows that birth cohorts in years considered auspicious are about 12% larger. This is evidence of birth behaviour influenced by cultural beliefs, not evidence that the zodiac sign determines destiny.
Why Is the Year of Birth Believed to Matter?
In Eastern thought, the year of birth is one of the four pillars (year, month, day, hour) that make up a birth chart. The heavenly stem and earthly branch of the year are believed to influence personality, fortune and compatibility among family members. Vietnamese Tử Vi (Vietnamese astrology) also distinguishes between good years for boys and good years for girls, based on the heavenly stem and earthly branch of the birth year compared with the parents' ages.
Many families believe that having a child in the Year of the Dragon, an auspicious year according to the heavenly stems and earthly branches, will bring luck, success and favourable prospects in marriage and career. Conversely, some years such as the Year of the Tiger or the Year of the Goat are considered less fortunate.
What Does the Research in Vietnam Say?
Quy-Toan Do and Tung D. Phung (2010), published in the American Economic Journal: Applied Economics, analysed birth data in Vietnam and found that birth cohorts in years considered auspicious were about 12% larger than in other years. The study also showed that children born in auspicious years had more years of schooling, but the authors note that this may be the result of parents investing more in children born in auspicious years, rather than the birth year itself.
In addition, Kim Dung Hoang (2013) presented an abstract at the IUSSP International Population Conference suggesting that the number of births in 2012 rose even though the overall fertility rate fell. This is a conference report that has not been peer-reviewed, and the figures have not been fully verified, so it should be assessed with caution.
East Asia: Common Patterns and Differences
Daniel M. Goodkind (1991) analysed data from Taiwan, Hồng Kông, Singapore, Malaysia and Chinese communities in the United States, finding that births rose clearly in the Dragon years 1976 and 1988. Paul S.F. Yip and colleagues (2002) also recorded a similar phenomenon in Hồng Kông: births rose in Dragon years and fell in Tiger years. Daniel Goodkind (1996) pointed out that in Singapore, timing births to the zodiac year increased along with modernisation, rather than decreasing.
Goodkind (1993) also found that in Taiwan in 1976, the main mechanism was adjusting the timing of marriage and birth behaviour, not just modern contraception. This shows that people actively arranged marriages and pregnancies so that their children would be born in the desired year.
However, in mainland China, Goodkind (1991) noted that the institutional conditions of the Cultural Revolution and the one-child policy prevented a birth surge in the Dragon years 1976 and 1988. Only in recent Dragon years (2000, 2012) have some new studies recorded the phenomenon of rising births again.
Chinese Communities in Malaysia and the Role of Minority Status
Daniel M. Goodkind (1995), published in Population Studies, analysed birth data of Chinese communities in Malaysia and found that this group concentrated births in Dragon years. Notably, in districts with a low proportion of Chinese residents, the custom of timing births to the Dragon year appeared more commonly. The author suggests that minority status may reinforce ethnic identity, and that this is reflected in birth behaviour as well.
Is Zodiac Belief Strong Enough to Be Used as a Natural Experiment?
Yes, according to James P. Vere (2008), published in the Oxford Bulletin of Economics and Statistics, birth fluctuations caused by the zodiac calendar are strong enough to be used as a natural experiment. He used these fluctuations to assess the effect of a first child on women's employment, and accordingly, the impact of the first child was found to be markedly larger than that of later children. In other words, belief in the zodiac itself created population fluctuations large enough for economic researchers to use as a measurement tool.
Summary Table of Evidence
| Study | Data scope | Main result | Level of evidence |
|---|---|---|---|
| Do and Phung (2010) | Vietnam | Birth cohorts in auspicious years about 12% larger; children born in auspicious years had more years of schooling | A |
| Goodkind (1991) | Taiwan, Hồng Kông, Singapore, Malaysia, Chinese communities in the United States | Births rose in the Dragon years 1976, 1988 | A |
| Goodkind (1993) | Taiwan, 1976 | Mechanism: adjusting the timing of marriage and behaviour, not modern contraception | A |
| Goodkind (1995) | Chinese communities in Malaysia | Births concentrated in Dragon years; timing births to the Dragon year more common in districts with a low proportion of Chinese residents | A |
| Goodkind (1996) | Singapore | Dragon years up, Tiger years down; timing births to the zodiac year increased with modernisation | A |
| Yip and colleagues (2002) | Hồng Kông | Births rose in Dragon years, fell in Tiger years | A |
| Vere (2008) | Data using the zodiac calendar as an instrumental variable | Birth fluctuations caused by the zodiac strong enough to be used as a natural experiment; the impact of the first child on women's employment larger than that of later children | A |
| Hoang (2013) | Vietnam, 2012 | Births rose even though the fertility rate fell (conference report not peer-reviewed) | B |
How Do People Time Births to the Zodiac Year?
Goodkind (1993) showed that in Taiwan, couples adjusted the timing of marriage so they could have a child in the Dragon year. Goodkind's (1991) research also recorded that the number of marriages rose in the two years before the Dragon year. In mainland China, provincial-level data for the period 2003-2013 show that marriages rose in the Tiger year and the Cat year (the two years immediately before the Dragon year), and births rose in the Dragon year.
What Does This Say About Belief and Behaviour?
The Dragon year effect is the clearest example of the saying "belief creates real behaviour". Belief in auspicious and inauspicious years is not just a notion; it has changed birth behaviour, marriage and investment in children. The measurable change in the number of births is evidence of the power of belief, not evidence that the zodiac sign determines destiny.
However, it should be noted that the evidence in Vietnam is based mainly on one study (Do and Phung 2010) and one conference abstract that has not been peer-reviewed (Hoang 2013). There is not yet a full analysis of the Giáp Thìn year 2024 in the existing sources. The results from Taiwan, Hồng Kông, Singapore, Malaysia or Chinese communities in the United States cannot be directly extrapolated to Vietnamese people without research on Vietnamese people.
Conclusion
Belief in auspicious and inauspicious years according to the zodiac has left traces in birth data in Vietnam and some East Asian countries. This is a real demographic phenomenon, reflecting behaviour influenced by culture. This article does not comment on families' decisions to have children, but only presents the existing research evidence.
