Kinship Inequalities Research Group, Max Planck Institute for Demographic Research, Rostock 18057, Germany.
Faculty of Economics, Actuarial Department, University of Buenos Aires, Buenos Aires C1120AAQ, Argentina.
Proc Natl Acad Sci U S A. 2023 Dec 26;120(52):e2315722120. doi: 10.1073/pnas.2315722120. Epub 2023 Dec 19.
Demographers have long attempted to project future changes in the size and composition of populations, but have ignored what these processes will mean for the size, composition, and age distribution of family networks. Kinship structures matter because family solidarity-a crucial source of informal care for millions of people around the world-is conditional on kin being alive. Here, we present innovative projections of biological kin for the 1950 to 2100 period and discuss what they imply for the availability of informal care. Overall, we project that the number of living kin for individuals will decline dramatically worldwide. While a 65-yo woman in 1950 could expect to have 41 living kin, a 65-yo woman in 2095 is projected to have just 25 [18.8 to 34.7] relatives (lower and upper 80% projection intervals). This represents a 38% [15 to 54] global decline. The composition of family networks is also expected to change, with the numbers of living grandparents and great-grandparents markedly increasing, and the numbers of cousins, nieces and nephews, and grandchildren declining. Family networks will age considerably, as we project a widening age gap between individuals and their kin due to lower and later fertility and longer lifespans. In Italy, for example, the average age of a grandmother of a 35-yo woman is expected to increase from 77.9 y in 1950 to 87.7 y [87.1 to 88.5] in 2095. The projected changes in kin supply will put pressure on the already stretched institutional systems of social support, as more individuals age with smaller and older family networks.
人口统计学家长期以来一直试图预测人口规模和结构的未来变化，但却忽略了这些过程对家庭网络的规模、结构和年龄分布意味着什么。亲属关系很重要，因为家庭团结——这是全世界数百万人获得非正式护理的重要来源——取决于亲属的生存。在这里，我们提出了 1950 年至 2100 年期间生物亲属关系的创新预测，并讨论了它们对非正式护理的可获得性意味着什么。总体而言，我们预测全世界个人的在世亲属数量将大幅下降。1950 年一位 65 岁的女性预计会有 41 位在世亲属，而 2095 年的同年龄段女性预计只有 25 位（80%置信区间为 25-34.7）。这代表全球减少了 38%（15-54%）。家庭网络的组成也预计会发生变化，在世的祖父母和曾祖父母的数量将明显增加，而表亲、侄子侄女和孙辈的数量将减少。由于生育率下降、生育时间推迟以及寿命延长，家庭网络的年龄结构也将发生显著变化，我们预测个人与其亲属之间的年龄差距将扩大。例如，在意大利，一名 35 岁女性的祖母的平均年龄预计将从 1950 年的 77.9 岁增加到 2095 年的 87.7 岁（87.1-88.5）。亲属供应量的预计变化将给本已紧张的社会支持制度带来压力，因为随着年龄的增长，越来越多的人与规模更小、年龄更大的家庭网络相伴。
