Popolazione mondiale:

Popolazione italiana:

Giovani (0-19 anni):

Anziani (60+ anni)

Troppi, o troppo pochi?

Con l’articolo di Joel E. Cohen e Joseph Chamie neodemos apre un dibattito sul tema dello sviluppo della popolazione del mondo e degli effetti sulle condizioni ambientali del pianeta, sull’economia e società dei vari paesi.

“È tempo di riconoscere che una crescita demografica più lenta arreca benefici all’America, alla Cina e alla Terra”, così scrivono Joel Cohen e Joseph Chamie in chiusura dell’articolo che oggi presentiamo ai lettori di Neodemos. I due autori commentano i risultati dei recenti censimenti di Cina e Stati Uniti, che mostrano un forte rallentamento della crescita demografica dei due paesi, così come sta avvenendo in altre parti del mondo, con l’eccezione dell’Africa sub-sahariana. Questa minore crescita, e l’eventuale declino che si prospetta in larga parte del globo, “segnala importanti e durevoli successi. È portatrice di implicazioni incoraggianti per il cambio climatico e l’ambiente. Le coppie hanno meno figli in un mondo sempre più urbanizzato, mentre uomini e donne perseguono istruzione, lavoro e carriere, e vivono più a lungo di sempre”.

Un tempo si sarebbe definito “maltusiano” il messaggio di Cohen e Chamie. Oggi le etichette non vanno più di moda, e convivono due visioni un tempo esclusive: la prima è che occorra moderare la crescita demografica del pianeta, che è direttamente associata con le emissioni di gas serra, con il riscaldamento globale, con l’occupazione disordinata dello spazio, e con molti altri aspetti del deterioramento ambientale. Alla fine del secolo, con diverse centinaia di milioni di terrestri in meno rispetto alle previsioni, gli stress ambientali sarebbero presumibilmente minori di quanto non si tema. L’altra visione sottolinea gli aspetti negativi di un sostenuto declino demografico, come si va prefigurando in vaste parti dell’Europa e dell’Asia orientale, legati all’invecchiamento e al suo costo, alla perdita di produttività e di innovazione, agli squilibri tra generazioni, e altro ancora. Potremmo dire che la prima è una visione macro, e top-down, che riguarda le sorti del pianeta, che va salvato con una robusta frenata della crescita demografica, o con una inversione della stessa. La seconda è una visione micro, bottom up, che riguarda le sorti di una nazione, di una regione, di una provincia che colpita dal declino demografico inverte la curva dello sviluppo. Temiamo i tre gradi in più della temperatura e, quindi, la desertificazione del territorio e l’innalzamento del livello del mare, ma temiamo anche la desertificazione umana e il rattrappimento della economia e della società.

Troppi o troppo pochi? È un dilemma che c’insegue da millenni e che ci tocca da vicino. L’Italia perde popolazione da sette anni e c’interroghiamo quanto a lungo durerà questo declino, e cosa porterà con sé, e come opporsi alle conseguenze negative. Ma l’Italia teme anche l’intensificarsi degli eventi metereologici eccezionali, la subsidenza della laguna di Venezia, l’inaridimento di parti cospicue del territorio, fenomeni cui la crescita della popolazione mondiale dà una robusta spinta. La crisi del pianeta si riflette sulle singole nazioni, ma la crisi di queste, in quanto dovuta al declino demografico, si riflette sulla capacità di opporsi alle malattie del pianeta.    

Slower population growth signals successes and benefits

Joel E. Cohen1 & Joseph Chamie2

Results from 2020 population censuses for the United States and China made headlines about population collapse, baby busts and demographic decline. Lopsided lamentations have given little attention to the social, economic and environmental benefits of slower growth. Joel E. Cohen and Joseph Chamie argue instead that the slowdown in population growth signals successes and benefits for America, China, and the Earth.

The past

Results from the 2020 population censuses in the United States and China recently made headlines. But rather than recognizing the social, economic, environmental and climatic benefits of slower rates of population growth for the U.S., China and the planet, much of the print and broadcast media in the U.S. stressed the downsides of slower growth and chose to write about population collapse, baby bust and demographic decline.

The U.S. population increase of 7.4 percent from 2010 to 2020 was the second lowest rate of growth since the country’s first census in 1790, and half the typical growth rates since 1790. Only during the Great Depression of the 1930s did U.S. population grow more slowly, by 7.3 percent. Even slower rates of growth are expected in the coming decades (Figure 1).

China’s population grew 5.3 percent in the decade ending in 2020, the lowest decadal growth rate since the catastrophic famine of the late 1950s. India projects for 2011-2021 its lowest decadal rate of population growth, 12.5 percent, since its independence.

The present

Lopsided lamentations have focused on the downsides of slower population growth. For example, some commentators who favor more rapid U.S. population growth contend that Americans would like to have more children than they are presently having. However, while this is the case for some American couples, others want fewer children. In 2011 (the latest available year), of the 6.1 million pregnancies in the United States, 1.6 million (27 percent) were mistimed and 1.1 million (18 percent) were unwanted at any time. Of all U.S. pregnancies in 2011, 45 percent were not intended (Guttmacher Institute 2019).

Some public handwringers maintain that a large population size aids the United States’ competition for economic and geopolitical dominance with China. But the mercantilist view that there is strength in numbers alone is obsolete by centuries. A large or rapidly growing population is hardly necessary or sufficient for prosperity.

Finland, ranked the happiest country in the world, has a total fertility rate of 1.4, compared to 1.6 in the U.S., 0.8 in South Korea, 1.1 in Singapore, 1.3 in Italy, 1.4 in Japan, 1.5 in Norway and 1.7 in Denmark. Women in China currently have 1.3 children on average, markedly fewer than in the United States (Figure 2).

The future

Some advocates of more rapid population growth argue that it would permit more people who want to migrate to the U.S. to do so. About 158 million adults in other countries would like to move and settle permanently in the U.S., according to the Gallup poll in 2018 (Esipova, Pugliese and Ray 2018). Would the U.S. willingly accept many or most of these would-be migrants?

More rapid population growth, especially through increased immigration of working-age adults, would temporarily ease the pressures on pay-as-you-go public programs for the elderly, particularly Social Security and Medicare in the U.S., by broadening the country’s tax base. But there’s a catch: in the future, those additional workers would retire, requiring additional workers to broaden the tax base again for the retiring workers. This demographic expansion would need to continue indefinitely.

Public discussion in the U.S. has largely ignored the notable social, economic and environmental upsides of slower American population growth. Slower population growth increases economic opportunities for women and minority groups, and exerts upward pressures on wages, especially for unskilled labor. For a given rate of capital investment, slower population growth also raises capital per person, raising productivity. The Gross Domestic Product (GDP) grows more slowly, but GDP per person grows faster.

All else equal, slower population growth lessens America’s contributions to climate change, biodiversity loss, deforestation, and pollution from commercial, industrial, agricultural, and domestic activities, such as heating and cooling buildings and fueling transport. Slower population growth makes it easier for governments, schools, and civic and religious organizations to respond more fully to increasing demands.

Worries about impending demographic doom for the U.S. seem decidedly misplaced. The United Nations (2019) projects that the populations of 55 countries or areas will decrease by 1 percent or more between 2020 and 2050. China’s population is projected to fall by almost 3 percent, Italy’s by 10 percent and Japan’s by 16 percent (Figure 3). By contrast, the population of the United States, currently at 333 million, is projected to grow by nearly 14 percent, largely through immigration, to 379 million by 2050.

The world’s population growth rate peaked in the 1960s and is falling in most regions except sub-Saharan Africa, which is the last major region to go through the demographic transition from high rates of mortality and fertility to relatively low rates. Whereas the U.S. population increased nearly four-fold during the 20th century, it is expected to increase by roughly 50 percent in the 21st century.

Conclusions

The United States and many other countries, including China, face real population challenges, but not principally slower population growth or even gradual population decline. These include addressing the needs of a rapidly aging population, managing cities and economies in recognition of climate change and environmental degradation, regulating and responding to migration, enabling people to have the children they want through reproductive health care and child-care support, and maintaining competitive technological change with better investments in education and worker training.

As COVID-19 has clearly demonstrated worldwide, real population challenges include protecting people against future pandemics and raising the value placed on today’s children, who are tomorrow’s problem solvers. In 2021, 22 percent of all children under age 5 years were stunted from chronic undernutrition (UNICEF, WHO, World Bank Group 2021), despite record cereal production globally (FAO 2021).

The global slowdown in population growth rates is not a transitory demographic problem: it signals important durable successes. It has encouraging implications for climate change and the environment. Couples are having fewer children in an increasingly urbanized world while men and women pursue education, employment and careers and live longer than ever before.

It is time to recognize that slower population growth benefits America, China, and the Earth.

Note

1 Joel E. Cohen – is Abby Rockefeller Mauzé Professor of Populations at The Rockefeller University and Columbia University in New York, USA

2 Joseph Chamie – Independent consulting demographer and former director of the United Nations Population Division

References

Agarwal, Kabir (2020) “India’s Population Will Be 1.52 Billion by 2036, With 70% of Increase in Urban Areas”.  13 August The Wire.

Esipova, Neli, Anita Pugliese and Julie Ray (2018) “More Than 750 Million Worldwide Would Migrate if They Could”.  10 December Gallup Poll.

FAO (2021) World Food Situation.

Finer, Lawrence B. and Zolna, Mia R. (2016) “Declines in unintended pregnancy in the United States, 2008–2011”.  New England Journal of Medicine 374:843-852.  DOI: 10.1056/NEJMsa1506575.

Guttmacher Institute (2019) “Unintended Pregnancy in the United States”.  January.

Shetty, Sudhanva (2021) “China’s 2020 Census Shows Population Barely Growing, Staring at Decline”. 11 May TRANSFIN.

U.S. Census Bureau (2021) “First 2020 Census Data Release”. 26 April.

U.S. Census Bureau (2020) “A Changing Nation: Population Projections”.

U.S. Census Bureau (1975) “Historical Statistics of the United States, Colonial Times to 1970”. Government Printing Office.

UN (2019) “World Population Prospects: 2019.” United Nations, Population Division. New York, NY.

UNICEF, WHO, World Bank Group (2021) Levels and trends in child malnutrition. Key findings.

PDFSTAMPA
Condividi questo articolo

Sostieni Neodemos


Cara Lettrice e caro Lettore, fare buona e seria divulgazione è il mestiere che esercitiamo da 15 anni con impegno e entusiasmo e, ci dicono, con autorevolezza. Dacci una mano a fare il nostro lavoro e rafforza la nostra indipendenza con un contributo, anche piccolo. Ci aiuterà a sostenere i costi di Neodemos, e ci incoraggerà a far meglio.

Grazie!

Iscriviti alla nostra newsletter


Due volta la settimana, riceverai una email che ti segnalerà i nostri aggiornamenti


Leggi l'informativa completa per sapere come trattiamo i tuoi dati. Puoi cambiare idea quando vuoi: ogni newsletter che riceverai avrà al suo interno il link per disiscriverti.

Potrebbero interessarti anche