51吃瓜

“It is exciting to do this kind of work at the UN, because of the central importance of population dynamics in all matters of social and economic development,” said John R. Wilmoth, who took office as Director of DESA’s Population Division on 2 January. In an interview, Mr. Wilmoth describes major population trends, his work on maternal mortality estimates and some surprising demographic developments.

With a distinguished academic background, Mr. Wilmoth has served as Professor at the University of California at Berkeley and has previously also worked for the Population Division as Chief of its Mortality Section from 2005 to 2007. He is the author or co-author of more than 50 scientific papers on various aspects of population dynamics and he was also the lead consultant to the World Health Organization for the development of new maternal mortality estimates, used for the monitoring of MDG 5.

How does it feel to be back at DESA and the Population Division?

“I am very glad to be back in DESA and the Population Division. Here I have many close friends and colleagues, whom I have known for many years. The staff of the Population Division is very talented, and I look forward to working with them (again). It is exciting to do this kind of work at the UN, because of the central importance of population dynamics in all matters of social and economic development.”

When looking at population trends across the globe, which major challenges and opportunities do you see?

“That is a very good question, because population trends do create challenges, but they also present opportunities. I think most people would agree that the three major trends are: population growth, population ageing, and migration (both within and between countries). Each of these presents important challenges to Member States and to the UN system, but we should not forget about the opportunities.

Take migration, for example: it can be a disruptive process for everyone involved (not only for the migrants themselves, but also for their communities of origin and destination). Yet, migration also serves many useful purposes: it reallocates labor resources from areas of surplus to areas of need, it creates numerous opportunities for the migrants themselves, and it fosters social and economic linkages between places of origin and destination. The challenge faced by policymakers is how to manage migratory flows so that the benefits can be enjoyed while minimizing negative impacts.

A similar principle applies in the case of population growth or ageing. It is seldom true that a particular population trend is inherently good or bad. Nevertheless, population trends are powerful forces that shape the social world in fundamental ways, and therefore we must be aware of what is happening and take appropriate steps to respond to the challenges that emerge from demographic changes.”

You have authored and co-authored a great number of scientific papers on population dynamics; were there any findings that you found surprising?

“Demographers often make projections of future population trends and can be surprised when reality diverges from their forecasts – but that is the nature of this business. An earlier generation of demographers was surprised by the extremely rapid growth of populations in the decades after the Second World War, which was caused by the Baby Boom in industrialized countries and by very rapid reductions of mortality in the less developed regions. For my generation I suppose the two biggest surprises have been the phenomenal speed and depth of fertility decline, and the persistent increase of human longevity.

Fertility levels have fallen substantially in most regions, far beyond what most observers expected 50 years ago. As a result, population growth has slowed considerably in many of the world’s largest countries, especially in Asia (though of course much less so in Sub-Saharan Africa). In many parts of Europe and East Asia, fertility is now well below two children per woman, and some populations have started to shrink in size. Such low fertility accelerates the process of population ageing, with substantial implications for government budgets given the high costs of old-age pensions and medical care.

Mortality trends have offered surprises too. Fifty years ago many observers believed that human longevity was reaching an upper limit, since by then most deaths (at least in the more developed regions) were due to diseases of old age. Since around 1970, however, death rates at older ages in many countries have been falling at an unprecedented rate. Reductions have been rapid in particular for deaths due to heart disease and stroke.

I expect that demographers will continue to be surprised by trends that do not follow our prior expectations. It is for this reason that the Population Division has worked hard in recent years to be more explicit and precise about the degree of uncertainty affecting projections of future population trends.”

As lead consultant for WHO, you have been part of developing new global estimates of maternal mortality to be used for the monitoring of MDG5. Could you share some details about this important work?

“A death that occurs in the process of creating life is a very sad and tragic event, with major consequences not only for the woman herself but also for her family, her community, and especially her surviving children. I believe it is for this reason that the UN system gives special emphasis to the issue of maternal mortality.

The only truly reliable way to track trends in maternal mortality is by means of a well-functioning civil registration system that gathers information on causes of death, but such data are available only for about 70 countries. For roughly 90 other countries, we can measure maternal mortality levels less precisely using various alternative forms of data (mostly sample surveys asking women about the death or survival of their sisters). Unfortunately, for about 30 countries there are no appropriate, national-level data for this purpose, and thus we rely on statistical models that allow us to “predict” levels of maternal mortality based on other social or economic variables, like personal income, fertility, and the proportion of births delivered by skilled attendants.

Despite these challenges of measurement, the latest estimates from WHO document a substantial decline in the risk of maternal death worldwide since 1990. However, this decline has been much faster in some regions than in others. This fact, combined with different regional trends in fertility, has produced a major shift in the global distribution of maternal deaths: in 1990 more than half of such deaths occurred in South Asia, but today more than half of all maternal deaths worldwide are happening in Sub-Saharan Africa.”

With your distinguished academic background and vast experience, what is your vision for the Population Division?

“The Population Division serves two key roles, both equally important and unique. First, we produce the “estimates of record” for monitoring world population patterns and trends, including projections of future trends. Our estimates of population size are a critical component of some of the most widely cited indicators used for monitoring social and economic development, including literacy rates and GDP per capita. One of my major goals as Director is to assure that the Division retains its preeminent place as the source of authoritative population data for the world, including information about levels and trends in fertility, mortality, international migration, and urbanization. In addition to relying on the excellent staff of the Division, I intend to continue a tradition of close collaboration with academic researchers.

Second, the Population Division services the intergovernmental discussion of topics related to population trends and processes, by producing authoritative studies, in-depth data analyses, and thoughtful interpretations and commentaries. Over the next few years, there will be several major political events in the area of population and development. The High-Level Dialogue on International Migration in October 2013 will focus attention on one of the major demographic trends of our time, while the Follow-up to the International Conference on Population and Development (ICPD+20) in 2014 will highlight the ongoing importance of programs in support of reproductive health and family planning. As DESA and the UN system move toward the adoption of a post-2015 development agenda, I intend for the Population Division to play a leading role in identifying issues, analyzing data, and shaping discussions about population trends and related social and economic processes.”