35Additionally, there are also sharp contrasts in terms of educational lev-
els between the three countries. In Lithuania, 69.9% of the population
have completed at least upper secondary school (in 2011), a share that
has more than doubled since 1970. Educational levels are also very high
in Switzerland: 48.3% of the population have upper secondary attain-
ment, a share that has been stable since the 1970s. In contrast, even
though some progress has been made in recent decades, in 2011 only
18% of the adult Portuguese population had completed upper secondary
school.
Looking once again at demographic trends, fertility rates have evolved
similarly in these three countries, with a clear decrease over recent decades.
In 2011, all countries experienced very low total fertility rates: Lithuania –
1.55, Portugal – 1.35, and Switzerland – 1.52. Portugal experienced the
highest drop in the total fertility rate since the 1970s: from 3.01 to 1.35
(for comparison: in Lithuania it fell from 2.40 to 1.55, and in Switzerland
from 2.10 to 1.52).
Declining fertility rates have been paired with an increase in the age of
women at first childbirth. In the beginning of the 1990s the mean age of
women at first childbirth was much higher in Switzerland (28.1 years)
than in Portugal (25.7 years) and especially than in Lithuania (23.2 years).
Over the last two decades, the mean age of women at first childbirth
increased in the three countries. However, that increase was much sharper
in Lithuania (+3.8 years) and Portugal (+3.5 years) than in Switzerland
(+2.5 years).
Meanwhile, there has been a remarkable increase in the proportion of
births outside marriage between 1979 and 2011: from 3.7% to 27.7% in
Lithuania, from 7.3% to 42.8% in Portugal, and from 3.8% to 19.3% in
Switzerland. This trend is especially noticeable since the 1990s. However,
there are differences in how fast the trend is moving. While Lithuania has
seen the fastest increase in births outside marriage, the biggest share of
births outside marriage is in Portugal, reflecting the deinstitutionalisation
of marriage in that country.
These developments draw attention to other demographic indicators
such as marriage and divorce rates. In Portugal and Switzerland, there has
been a steady decrease in crude marriage rates: from 1970 to 2011 the
crude marriage rate fell from 9.4 to 3.4 in Portugal and from 7.6 to 5.3 in
Contextualising Personal Networks Across Birth Cohorts...