From Eurostat [PDF], which notes:
The European Union (EU) as a whole is confronted with an ageing population. In 2014, the proportion of persons aged 65 or over reached 18.5% in the EU and it is projected to further increase in the future to almost 30% by 2080. In particular, the proportion of persons aged 80 or over among the total population is expected to more than double, from just over 5% in 2014 to more than 12% by 2080. This demographic trend confronts the EU with major challenges, notably regarding the economic situation and social inclusion of older people.
In 2014 in the EU, 18.5% of the population was aged 65 or over, including around 5.1% aged 80 or over. Member States with the highest proportions of population aged 80 or over were Italy (6.4%), Greece (6.0%), Spain and France (5.7% each). Conversely, the lowest proportions were found in Ireland and Slovakia (both with 3.0% of their population aged 80 or over) as well as in Cyprus (3.1%).
The proportion of the EU population aged 80 or over has risen over the last 15 years, from 3.5% in 2001 to 5.1% in 2014. Population projections show that the EU population will age further: by 2080, almost 1 out of every 8 persons (12.3% of the population) would be aged 80 or over. Slovakia (now the Member State with the lowest proportion) is projected to become the Member State with the highest share of persons aged 80 or over (16.3%), followed by Portugal (15.8%), Germany (15.1%) and Poland (14.9%). At the opposite end of the scale, Ireland (with 7.4% of the population expected to be aged 80 or over by 2080), Lithuania (8.9%) and Latvia (9.5%) would have the lowest shares.