According to the 2015 Inter-census Survey, the total population in Mexico was 119,938,473 persons, of which 51.4% were women and 48.6% men. There are 94.4 men for every 100 women. The median age of the population was 27 years (INEGI, 2015b). The structure of the population reflects the interaction between the birth rate and mortality over time. Comparing the population structure by age in the years 2000 and 2015, we observe the typical pattern followed by ageing societies where the younger population groups decrease (the base starts shrinking) while middle age and older age groups increase. For the first time in 2015, the numbers of people aged 60 years and older is larger than the numbers aged 0 to 4 years old, which indicates a decrease in the proportion of children and an increase in older adults. Older people represent 5% of the total population for the year 2000, and 6.2% in 2010, and 7.2% in 2015 (INEGI, 2015c).

The median age for 2015 was 27 years, a notable increase from the 22 years reported in the year 2000. However, there are notable differences between the different states, reflecting the heterogeneous development, economic transition, and ageing process in each state. For example, in the state of Chiapas, located in the south of the country, the median age is 23 years, while for Mexico City it is 33 (INEGI, 2018b). This heterogeneity is also observed in the aging index^[2]. In 2015, while on average there were 38 adults 60 years and older per 100 children, there were 62 in Mexico City and 24 in the state of Chiapas (González, 2015). 

Old-age dependency ratio

The total dependency ratio^[3] in Mexico in 2015 was 53 older adults per 100 younger individuals. Traditionally international organisations have used this ratio to express how those who are assumed to be not economically independent (the youngest and the oldest population groups) depend on those who are (adolescent and younger adults), it is clear that worldwide this is not necessarily true as both groups have changed significantly. On one hand, young adults in many countries do not move out of the parental household as early as they did in the past, continuing to be dependent on their parents, and on the other hand, large percentages of older adults continue to be physically and economically independent well beyond the age of 60 or 65, and therefore alternative estimations have been considered (United Nations, Department of Economic and Social Affairs, 2017b).

There is variation in the dependency ratio between states within the country, the state of Chiapas has the highest total ratio of dependence, 64 per 100 people of working age, and this can be attributed to a high level of fertility. On the other hand, migration also affects this indicator, since there are states with a high reception of working-age population, such as Quintana Roo, Baja California Sur, and Queretaro. While Mexico City has a low ratio of total dependence, it has the highest dependency ratio in old age compared to the other states of the country (INEGI, 2015c).

Fertility

The rapid demographic transition currently taking place in the country reflects the decline in fertility in the last decades, going from a Global Fertility Rate (GFR) of 5.73 children born alive per women 15 to 49 years old, to a GFR of 1.9 in the year 2000, and 1.7 in 2015, with a total decrease of 31.8% in the number of children born alive (INEGI, 2015b). Socioeconomic situation and women’s education have a differentiated impact on GFR, while women with low or no educational attainment have an average of 3.2 children, women with medium and higher level of education have 1.1 (INEGI, 2015b). However, Mexico had an increment in adolescent pregnancies (among women aged 15 to 19) which grew by almost 6 points between 2009 and 2015 (INEGI, 2015b). Women living in larger urban areas had lower global fertility rates than those living in urban centres with less than 100,000 in habitants (2.0 vs 2.8 respectively) (INEGI, 2015b).

[2] The aging Index is estimated as the ratio of population 60 years and older for every 100 individuals less than 15 years.

[3] For Mexico, INEGI estimates the dependency ratio by dividing total of household members who are not of working age (0 to 14 and 60 years and older) by the total of those considered of working age (15 to 59 years old).

References:

González, K. (2015). Envejecimiento demográfico en México: análisis comparativo entre las entidades federativas. In La Situación Demográfica de México 2015 (pp. 113–129). Consejo Nacional de Población. http://www.conapo.gob.mx/work/models/CONAPO/Resource/2702/06_envejecimiento.pdf

INEGI. (2015a). Censo de Alojamientos de Asistencia Social. https://www.inegi.org.mx/programas/caas/2015/

INEGI. (2015b). Encuesta Intercensal 2015 Estados Unidos Mexicanos. Instituto Nacional de Estadística y Geografía, 1, 85–90. http://internet.contenidos.inegi.org.mx/contenidos/Productos/prod_serv/contenidos/espanol/bvinegi/productos/nueva_estruc/702825078966.pdf

INEGI. (2015c). Mortalidad. Esperanza de vida al nacimiento por entidad federativa.

INEGI. (2018b). INEGI. Datos. https://www.inegi.org.mx/datos/

United Nations, Department of Economic and Social Affairs, P. D. (2017b). World population prospects: the 2017 revision. Volume II: Demographic Profiles, 2, 1–883. https://population.un.org/wpp/publications/Files/WPP2017_Volume-II-Demographic-Profiles.pdf