Diane Macunovich’s article “Relative Cohort Size: Source of a Unifying Theory of Global Fertility Transition” offers new evidence to further the work advanced by Richard Easterlin in the 1960s and 70s. Macunovich’s goal is to produce evidence to support a unifying theory of global fertility transition. This is a difficult accomplishment, as fertility seems so tied to cultural and domestic factors. Yet Macunovich, by analyzing United Nations world population data, was able to describe a simple mechanism that can account for fertility transition in an overwhelming number of countries at which she looked. What she describes is a mechanism whereby relative cohort size (RCS) affects the total fertility rate (TFR). Her argument uses Easterlin’s hypotheses on the Supply-Demand Framework and RCS and uses them to explain the initiation point of the change in TFR. This is all supported with rigorous analysis and stable evidence, by accounting for both the conformist and nonconformist cases and other variance.
The analysis begins with a look at the supply-demand framework and the relative cohort size hypothesis. These are discussed as the jumping points for the Macunovich’s analysis. The supply-demand framework divides demographic transition in five phases. In this mechanism, the excess supply of children is the motivating factor in controlling fertility in a society. The key problem with this framework, as Macunovich clearly points out, is that by the fourth phase, excess supply is no longer a factor, and therefore does not explain why there is a continued decline in demand in the fourth and fifth phases,. This is what Macunovich is seeking to explain, using the supply-demand as the conceptual framework for her argument.
This brings us to a more robust mechanism, as described by Macunovich. A pre-transition society will first experience a drop in infant mortality due to better health. This in turn causes an increased relative cohort size as more children live to adulthood. The result is a relative decline in wages. This focus on relative decline as opposed to absolute decline is an important distinction that Macunovich is making. A relative decline will then go on to explain why young people will seek to delay marriage, or forgo having children, in order to maintain their standard of living inherited from their upbringing. Economists in the past have missed this key motivating factor because they, again, focused on the absolute wage.
Macunovich then continues to explain the fourth and fifth phases described in the supply-demand framework with which we began. Here she draws from the economic concept of sticky prices. Hence, even once the RCS subsides, there is a depressing effect of a slowdown of the economy due to the change in cohort size again and thus accounts for the lag. Likewise, there is a cascade effect on the cultural norms of the society that also holds back TFR. It is the relative measure of cohort size that drives her mechanism. So RCS is playing a role in both decreasing the TFR of a country, but also then, in keeping the TFR low in this linear progression.
After laying out this mechanism, Macunovich then turns to the data. The strength of her argument really lies in the methodology involved in her analysis of the data. She clearly accounts for all situations, by singling out counties that do not always conform to her hypothesis. Another key aspect to this study is that she not only looks at developed nations, but she endeavors to include developing nations, thus making this a truly global fertility theory. The challenge exists, which is discussed briefly, that developing nations have yet to finish this progression. Through both graphical and regression analysis, Macunovich proves that RCS drives the fall of the TFR and is even able to derive the point of initiation. Her evidence is stable, in that this point of initiation can be derived regardless of infant mortality rate.
Macunovich has made an important contribution to the economic understanding of fertility transition. In her work, she uses the conceptual framework set forth by Richard Easterlin to provide a clear and concise mechanism for fertility transition that can be proven over a wide variety of data.