# Changing generational tides: the transformation of electoral participation in European Parliament elections

Chiao Li

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# Changing generational tides: the transformation of electoral participation in European Parliament elections

Chiao Li

**To cite this article:** Chiao Li (14 Aug 2024): Changing generational tides: the transformation of electoral participation in European Parliament elections, West European Politics, DOI: 10.1080/01402382.2024.2382020

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# Changing generational tides: the transformation of electoral participation in European Parliament elections

Chiao Li ID

Centre for European Studies and Comparative Politics, Sciences Po, Paris, France

## ABSTRACT

Electoral turnout has been declining in nearly all Western democracies. While scholars have identified the 'negative' effects of generational replacement and forecasted how turnout will continue to decline, the turnout in the 2019 European Parliament election surged to its highest participatory level in the last two decades, driven surprisingly by increased youth participation. This age-period-cohort study investigates whether and to what extent younger generations socialised in changing electoral contexts turn out at different levels than their generational counterparts. Analysing survey data from the EES and the CSES across 28 European countries over decades reveals a reversing generational participatory pattern in EP elections and a narrowing turnout gap between national and European Parliament elections across younger generations, despite differences in Western and Eastern Europe. These results have important implications for the effect of generation on turnout and future trends of electoral participation.

**KEYWORDS** Turnout; electoral behaviours; European Parliament; voting behaviour; youth

The decline in electoral turnout had been a prevailing trend across advanced democracies during the latter half of the twentieth century, affecting national elections (Gray and Caul 2000) and European Parliament (EP) elections (Flickinger and Studlar 2007). Existing research has shown that generational replacement is a contributing factor to this decline, suggesting an adverse impact of generational turnover on overall turnout (Bhatti and Hansen 2012; Blais et al. 2004; Gallego 2009; Konzelmann et al. 2012; Wass 2007a, 2007b).

Scholars had anticipated a continued electoral decline in EP elections based on lower turnout levels among post-baby boomers (Bhatti and Hansen 2012). In a surprising twist, the turnout in the 2019 EP election

## CONTACT

Chiao Li chiao.li@sciencespo.fr

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Supplemental data for this article can be accessed online at https://doi.org/10.1080/01402382.20

24.2382020.

© 2024 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.

This is an Open Access article distributed under the terms of the Creative Commons Attribution-NonCommercial-NoDerivatives License (http://creativecommons.org/licenses/by-nc-nd/4.0/), which permits non-commercial re-use, distribution, and reproduction in any medium, provided the original work is properly cited, and is not altered, transformed, or built upon in any way. The terms on which this article has been published allow the posting of the Accepted Manuscript in a repository by the author(s) or with their consent.
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departed from these projections, surging to its highest participatory level in the last two decades. Immediate analysis of the 2019 EP election has, at least partly, attributed the increased turnout to rising youth participation (Becewe et al. 2019). Yet, the 2019 EP election, occurring in the aftermath of the Brexit referendum and amid global student protests advocating for climate change action, may also be influenced by the presence of period effects leading to surging turnout across all age groups. The inconsistency between scholarly forecasts based on previously identified generational turnout patterns and the actual turnout development in recent EP elections prompts the question of where this increased youth participation came from: Did individuals from all generations exhibit an increased propensity to vote, or were there distinct patterns emerging among younger cohorts?

Extensive research has disentangled the electoral participation disparity between pre- and post-baby boomers (Blais et al. 2004; Franklin 2004; Gallego 2009; Wass 2007a, 2007b). Yet, the question persists as to whether and to what extent recent cohorts turn out at different levels than their generational counterparts. This puzzle arises from the notable divergence between scholarly forecasts grounded in generational turnout trends and the observed turnout outcomes in recent EP elections. Whereas it is tempting to focus on the short-term forces shaping the twists and turns of turnout in recent EP elections, I stepped back to take a generational view of how changes in generational composition have affected aggregate turnout.

This 'age-period-cohort' (APC) study investigates the long-term transformation of electoral participation through the lens of generations. Employing the European Election Studies (EES) 1989-2019 and the Comparative Study of Electoral Systems (CSES) Modules 1-5, this research identifies and compares how various cohorts participate in national and EP elections across 28 European countries over decades. Contrary to the widely observed 'negative' effects of generational replacement on aggregate turnout (Bhatti and Hansen 2012; Blais et al. 2004; Gallego 2009; Wass 2007a, 2007b), it reveals a reversing generational participatory pattern driven by increased participation among younger cohorts in EP elections.

Furthermore, it demonstrates a narrowing gap in turnout between European and national first-order elections across younger generations, explained by their decreasing likelihood of becoming EP-only abstainers – those participating in national but abstaining in European contests. While the second-order election (SOE) model remains the dominant paradigm for comprehending electoral dynamics in EP elections (Reif and Schmitt 1980; Schäfer 2021), the narrowing turnout gap between domestic and supranational arenas across younger cohorts suggests a changing character of present-day EP elections in the view of younger voters.
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This article commences with speculation about changing generational participatory patterns in EP elections. Subsequently, it outlines the theoretical framework and hypotheses linking cohort differences in electoral participation to different socialisation experiences. Following this, it presents the data and methods employed. The results section identifies and compares turnout patterns in European and national elections across generations, investigating the extent to which individuals from different cohorts participate and abstain in national and EP elections. Finally, it concludes with the findings and their implications for ongoing electoral dynamics in Europe.

# Electoral shifts and generations

## Changing generational turnout dynamics?

Interested in explaining declining turnout patterns, political scientists have delved into three temporal effects: age, period, and generation (Franklin 2004), highlighting the consequences of an adverse impact of generational replacement (Blais et al. 2004; Gallego 2009; Wass 2007a, 2007b). Examining the variance in aggregate turnout from 1968 to 2000 in Canada, Blais et al. (2004) confirm substantial age and generational effects, accompanied by a marginal period effect affecting voters across all demographic groups.

A curvilinear relationship between age and turnout has been observed in survey data since the very first election studies (Wolfinger and Rosenstone 1980)¹; as citizens age, their likelihood to vote increases but gradually decreases in old age. Scholars have often interpreted this pattern as reflecting transitions in the life cycle. The middle-aged are more likely to vote as they acquire more resources, take on adult roles, and establish longer-term residence (Goerres 2007; Highton and Wolfinger 2001); conversely, elderly citizens gradually face health challenges, live without a spouse or children, and disengage from social life, leading to a decline in both resources and social pressure to vote (Fieldhouse and Cutts 2012).

In addition, turnout differs among various cohorts, even within comparable life stages. A marked discrepancy in electoral participation is widely identified between pre- and post-baby boomers (Blais et al. 2004; Franklin 2004), explained by a weaker sense of civic duty and lower interest in politics (Blais and Rubenson 2013; Dalton 2009). Nevertheless, as age compositions remain relatively consistent despite a gradually ageing population, lower participation levels among post-baby boomers are found to be the primary factor contributing to the decline in aggregate turnout (Bhatti and Hansen 2012; Blais et al. 2004). Yet, considering age effects is essential to properly identifying generational differences.
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Similar findings regarding the curvilinear effect of age in survey data and the adverse impact of generational replacement on turnout have been observed in national elections in Finland (Wass 2007b), Sweden, Norway, and Germany (Gallego 2009), as well as in EP elections across EU member states (Bhatti and Hansen 2012). Several scholars have endeavoured to forecast changes in future voter turnout, drawing from estimated effects of age and generation and shifting age and generational compositions. Their predictions generally point towards an ongoing decline in participation in national and European elections. For instance, based on the significant adverse cohort effects in German federal elections from 1952 to 2009, Konzelmann et al. (2012) forecast an ongoing electoral decline, even considering an ageing population. Additionally, identifying post-baby-boomer cohorts as less electorally active in EP elections from 1979 to 2009, Bhatti and Hansen (2012) anticipate a continued turnout decline in EP elections mainly due to future shifts in generational compositions.

However, contrary to scholars' projections of a persistent turnout decline, the 2019 EP election witnessed a surge to its highest participatory level in the last two decades. The average voter turnout across EU member states examined in Bhatti and Hansen's study (2012) saw an unexpected increase of 1.5%. This surge departed from the anticipated turnout decrease of 2.5%, as Bhatti and Hansen (2012) projected, under the assumption that future generations would vote at the same rates as the cohort currently eligible in the 2009 EP election (those born between 1980 and 1991).² Surprisingly, more than half of these countries experienced a notable increase in voter turnout, with Spain and France showing the most significant surges (see Table 1).

This discrepancy between actual results and electoral forecasts from previously identified generational participatory patterns adds complexity to understanding turnout dynamics in EP elections. It raises the question

<table><caption>**Table 1.** Predicted and actual turnout changes in EP elections over time (%).</caption><thead><tr><th></th><th>Predicted turnout from 2009 to 2020</th><th>Actual turnout from the 2009 to 2019 EP elections</th></tr></thead><tbody><tr><td>Belgium</td><td>-2.1</td><td>-1.9</td></tr><tr><td>Britain</td><td>-1.3</td><td>2.4</td></tr><tr><td>Denmark</td><td>-1.0</td><td>6.6</td></tr><tr><td>France</td><td>-0.5</td><td>9.5</td></tr><tr><td>Greece</td><td>-3.8</td><td>6.1</td></tr><tr><td>Ireland</td><td>-3.9</td><td>-7.9</td></tr><tr><td>Italy</td><td>-6.0</td><td>-10.5</td></tr><tr><td>Luxembourg</td><td>-0.7</td><td>-6.7</td></tr><tr><td>Netherlands</td><td>-2.0</td><td>5.1</td></tr><tr><td>Portugal</td><td>-2.1</td><td>-6.0</td></tr><tr><td>Spain</td><td>-4.3</td><td>19.4</td></tr><tr><td>Average</td><td>-2.5</td><td>1.5</td></tr></tbody></table>

Note: Predictions are based on Bhatti and Hansen (2012, first model in Table 6, p.270), while the actual turnout is calculated using data from the International IDEA Voter turnout database.
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of whether the flattened turnout decline can be partly attributed to chang-
ing participatory levels across younger cohorts. This investigation is criti-
cal to understanding turnout development in European elections because
period and cohort effects have different implications. While period effects
suggest short-term fluctuations of aggregate turnout, cohort effects inform
long-term turnout trends affected through generational replacement.

***Changing second-order character of EP elections?***

The turnout dynamics in EP elections have traditionally been studied in connection to national first-order elections. EP elections have been predominantly regarded as second-order national arenas fought under the shadows of national elections since their first appearance in 1979 (Reif and Schmitt 1980; Schäfer 2021). The lower turnout in European elections than national ones represents one central feature of the second-order election (SOE) model (Schmitt et al. 2020).

Confronted with the changing contexts of EP elections in recent decades, scholars have attempted to assess the temporal robustness of the SOE model. However, the second-order characteristics of the EP elections, including turnout disparity between national and European elections, remain hardly denied through aggregate-level analysis (see Schmitt and Toygür (2016) for the 2014 EP election; Hix and Marsh (2011) for the 2009 EP election; Schmitt (2005) for the 2004 EP election; Hix and Marsh (2007) and Marsh (1998) for an overview).

The temporal robustness of the SOE model has, however, been increas-
ingly questioned with individual-level analysis, ranging from experimental
surveys (Hobolt and Wittrock 2011) to panel data in a single member
state (Boomgaarden et al. 2016) to waves of cross-national post-electoral
surveys (Schäfer and Debus 2018; Schmitt et al. 2020). Concerns about
the European polity have recently found increasing evidence in voting
decisions in EP elections (Braun 2021; Hobolt and Spoon 2012; Schäfer
and Debus 2018). Interested in explaining the persistent turnout gap at
the national and EU levels, some scholars have investigated different
motivations for participating and abstaining in national and European
elections (Schäfer 2021; Stockemer and Blais 2019). However, examining
turnout dynamics in national and European elections through the lens of
generational differences remains lacking yet relevant.

The evolving second-order nature of EP elections has not received ade-
quate attention regarding cohort differences. If early electoral experiences
determine habits of voting or non-voting (Franklin 2004) and later stages
of life are accompanied by increased attitudinal stability (Dinas 2013),
changes in the character of present-day EP elections may be more brought
about through generational replacement. This research employs the
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analytic lens of cohort differences but applies it in a novel way to examine the changing character of present-day EP elections. It explores the dynamics of the turnout gap at the national and EU levels across generations, emphasising the importance of socialisation experiences in shaping levels of electoral participation in national and EP elections.

# Theoretical framework and hypotheses

## Political socialisation and youth sensitivity to changes

Grounded on the theory of political socialisation, generational differences in attitudes and behaviours are attributed to the changing socio-historical contexts in which individuals are exposed during their formative years. The underlying theoretical foundations are two-fold. Regarding timing, the period from late adolescence to early adulthood is seen as a critical juncture when political beliefs, opinions, and predispositions are developed, challenged, and ultimately crystallised; in contrast, later stages of life are typically accompanied by an exponential increase in attitudinal stability (Dinas 2013). While the literature lacks consensus regarding the precise age at which young adults are most significantly affected by political events (Grasso 2014; Neundorf and Smets 2017), a detailed panel study conducted among Dutch adolescents and young adults suggests that the most influential period for shaping voting behaviour occurs around the age of 18 (Rekker et al. 2019).

Regarding causes, the effect of generation is associated with changing contexts of political socialisation. It leads to the crystallisation of different values, attitudes, and behaviours among cohorts. Differences across generations can be direct consequences of particular socio-historical events (Mannheim 1928), as the student protests of 1968 are demonstrated to contribute to political activism among those coming of age in Western Europe (Grasso 2016). They can also result from latent social transformation in general circumstances during individuals’ formative years (Inglehart 1977). For instance, Kostelka and Blais (2021) show that affluent conditions in post-industrial societies have imprinted lower voter turnout among those coming of age.

Once politically socialised, individuals tend to behave relatively similarly in elections, which could be interpreted as forming voting habits (Dinas 2012) or reflecting steady attitudes (Kostelka and Blais 2021). Although all cohorts at a given time may live in a similar political context shaped by socio-historical events, they arguably experience different degrees of exposure. While changes create an additional layer of crystallised attitudes and habits among older voters, they potentially leave an imprint on the young without prior experience (Dinas 2013). The
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prominent role of political socialisation during formative years and its
lasting impact on voting behaviour have found empirical evidence. For
instance, elections of low salience are shown to imprint low turnout
among the young, as early electoral experience determines voting and
non-voting habits (Dinas 2012; Franklin et al. 2004; Smets and
Neundorf 2014).

Changing EP electoral contexts during the formative years of
younger cohorts

During the formative years of earlier generations, European electoral are-
nas were arguably less consequential and showed little concern for the
contestation over European issues. However, the electoral contexts of
recent EP elections in which younger generations were politically social-
ised appear no longer identical. While scholars continue to debate the
second-order character of present-day EP elections (Hix and Marsh 2007;
Schäfer 2021), there is general agreement that the EU and its parliament
have undergone significant transformations at the turn of the twenty first
century (Hix and Marsh 2011; Schmitt 2005). The expanded reach of the
EU and the increased significance of European issues have arguably led
to less depressing participation in supranational contests across younger
cohorts socialised in the changing electoral contexts of EP elections in
recent decades.

The policy scope of the EU has dramatically widened during the for-
mative years of younger generations amidst the shift to the 2000s.
Successive EU treaties, including those of Amsterdam, Nice, and Lisbon,
were implemented in the post-Maastricht period. The establishment of the
European Central Bank in 1998 and the introduction of the euro in 1999
marked significant milestones. In contrast to the European Coal and Steel
Community established in 1952, studies indicate that, by the 1990s,
Brussels began producing more than half of the significant legislation,
surpassing any other national capital (Schmitt 2005).

In addition, the geographical range of the EU expanded considerably
through various stages of enlargement, which changed the electoral con-
texts of EP elections in which younger cohorts were socialised during
their formative years. While 9 countries initially participated in the first
EP elections in 1979, 15 nations took part in 1999. It then surged to 25
members, with 10 Eastern European countries joining the EU through the
2004 enlargement.

Moreover, the growing power of the EU, coupled with the increased
salience of European integration, has arguably contributed to the rising
significance and Europeanisation of EP elections during the formative
years of younger cohorts in recent decades. Initially described as a
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‘sleeping giant’ capable of sparking political contestation in the late 1990s (Franklin and van der Eijk 1996), the issue of European integration no longer fosters permissive consensus but instead constrains dissensus (Hooghe and Marks 2009). Its salience has increased through the European sovereign debt crisis emerging in 2008 and the migration crisis peaking in 2015 (Hooghe and Marks 2018; Otjes and Katsanidou 2017). Compared to the poor media coverage of previous EP elections (de Vreese et al. 2006), news coverage of the 2009 EP election witnessed an exponential increase across EU member states (Schuck et al. 2011).

In the first EP elections, it is asserted that ‘those who participated went to the polls just because they are used to doing so on election day’ (Schmitt and Mannheimer 1991: 31). In contrast, when queried about the motivations for turnout and party choice in the 2019 EP election, respondents of younger ages are more likely to attribute their participation to a desire to make changes and a sense of European identity or EU citizenship; additionally, their party preferences exhibit greater susceptibility to stances related to European issues and the EP electoral campaign (Becewe et al. 2019). Given the widened reach of the EU and the heightened significance of European issues in the developmental epochs of more recent generations, I thus expect that younger cohorts, compared to earlier cohorts, are not monotonously less likely to participate in European Parliament elections.

**H1:** The probability of voting in European Parliament elections does not decline from earlier cohorts to later cohorts.

Whereas recent empirical evidence from certain EU member states may suggest an increased turnout in national first-order elections among younger age groups,³ it appears more plausible that turnout trends across generations diverge between national and supranational arenas in general across countries. While the declining trend in turnout reversed for the first time in the 2019 EP election, the turnout in national first-order elections continues to experience a general erosion in electoral participation (see Figure 1). On the basis of the influential role of early electoral experiences in shaping voting habits (Dinas 2012; Franklin 2004), it is less likely that recent national elections have exceptionally high salience and have imprinted high turnout among the youth coming of age.

Additionally, the impact of general economic affluence in post-industrial societies has arguably induced a cultural shift among subsequent cohorts, leading to a latent transformation of citizens’ values and attitudes (Inglehart 1977). Post-baby boomers are characterised by a weakened sense of civic duty and diminished interest in politics (Blais and Rubenson 2013; Dalton 2009). Moreover, with a substantial increase in voting opportunities for individuals socialised over the years, the increasing emphasis on
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<figure><img src="image_24.png" /><figcaption>**Figure 1.** Turnout trends in national and European elections over time.</figcaption></figure>

Note: The voter turnout figures include national first-order and EP elections held across the EU-28 from 1975 to 2019, sourced from the International IDEA Voter turnout database. The general turnout trends represent the average turnout rates of all elections held across countries over a quinquennial period. The turnout gap represents the difference in these average turnout rates between EP and national first-order elections. Unlike in other EU member states, in France and Romania, presidential elections are considered national first-order rather than national parliamentary elections.

multilevel governance and the frequent use of referendums in recent decades have arguably diminished the importance of national first-order elections (Kostelka and Blais 2021). Due to the fundamental shifts in how later cohorts socialised in post-industrial societies perceive and engage in national elections, together with the observed general turnout decline, I hypothesise that younger cohorts are less inclined to participate in national first-order elections compared to their predecessors.

H2: The probability of voting in national first-order elections declines from earlier cohorts to later cohorts.

The speculated declining turnout trend in national contests across generations, contrasting with the rising participation among younger cohorts in EP elections, suggests a narrowing turnout gap among younger generations between national and European elections. Theoretically, the aggregate turnout gap at these two levels of elections results from individuals participating and abstaining differently in these contests at the micro level (i.e. those participating in national elections but not in EP elections and those participating in EP elections but not in national elections). In a nutshell, different turnout rates at the national and EU levels would not exist in the first place if all individuals either participated or abstained in national and European contests.

Based on voters' turnout decisions in a supranational election and its previous (or concurrent) national election, voters can be categorised into four groups: (1) voters (i.e. those who participate in national and EP elections), (2) EP-only abstainers (i.e. those who participate in national elections but not in EP elections), (3) EP-only voters (i.e. those who abstain in national elections but not in EP elections), and (4) habitual abstainers
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(i.e. those who abstain in national and EP elections). While the EP-only abstainers represent 26% and 19% of the overall sample in the 2014 and 2019 EP elections across the EU-28, the EP-only voters account merely for 5% of the electorate (Schmitt et al. 2020). Therefore, if the narrowing turnout gap across younger generations is observable, it should be primarily reflected in the declining likelihood of becoming an EP-only abstainer among younger cohorts. This leads to the third hypothesis concerning the changing dynamics between national and EP elections across generations.

H3: The turnout gap between national and European Parliament elections narrows across younger cohorts, with a decreasing likelihood of becoming an EP-only abstainer among younger cohorts.

# Data, operationalisation, and methods

## Data

Individual-level turnout data is taken from European Election Studies (EES) from 1989 to 2019 and the Comparative Study of Electoral Systems (CSES) Modules 1–5. These datasets jointly provide turnout data in national and EP elections over decades across 28 European countries (previously grouped as the EU-28). The EES contain survey data on supranational elections held over time, except for a few first EP elections held separately within new member states outside the regular 5-year interval.⁴ The CSES M1–5 provides survey data on national first-order elections from 1996 to 2020, including presidential elections in France and Romania and parliamentary elections in other EU member states. Although the CSES does not cover all national first-order polls across the EU-28, additional turnout information in domestic contests is available in the EES, which also contains questions about individuals’ last electoral participation in national elections (see Figure 2 for the availability of turnout data).

The EES and the CSES provide valuable data on voter turnout across various countries, utilising standardised methodologies. Despite efforts to minimise bias and measurement error, self-reported turnout in surveys suffers from over-reported participation due to social desirability bias. Yet, this issue is considered less problematic in this study as its primary focus lies in comparing relative voting probabilities across generations rather than their actual values. There may be limited avenues for intervention; however, potential bias in the results could arise if there are variations in social desirability norms across generations. Analyses conducted with weighted data adjusting for sample distributions of socio-demographic
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<figure><img src="image_27.png" /><figcaption>Figure 2. Overview of turnout data included in the analysis.</figcaption></figure>

characteristics and discrepancies in reported turnout and official vote counts yield similar results.⁵

## Strategy for identifying generational effects

This study employs a so-called APC analysis to identify and compare the effect of generation on turnout in national and EP elections over time. However, given that three temporal effects, age, period, and generation, are linearly dependent (Cohort = Period - Age), models cannot be identified without requiring some form of theoretical assumption about at least one of the three APC effects (Neundorf and Niemi 2014).

Given that the age effect, reflecting transitions in the life cycle, is one of the most important independent variables explaining variation in individual turnout (Smets and van Ham 2013) and that its curvilinear effect is observed in survey data (e.g. Bhatti and Hansen 2012; Gallego 2009; Wass 2007b), the continuous age variable and its squared term are included in APC models to control for the impact of ageing.⁶ On the other hand, period effects are categorised into dummies of each country and election year (i.e. country-year combinations).⁷ While each national election is nested in each country and election year, turnout decisions in EP elections are also influenced by country-year-specific episodic factors. These short-term effects include the timing of EP elections relative to national contests in each EU member state, the participation boost in the first EP elections held in new EU member states (Franklin 2001), and the concurrence of salient domestic referendums with EP elections.⁸
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Yet, the APC identification problem has spurred substantial method-
ological literature with various approaches proposed to overcome it (see
Achen and Wang (2019) for an elegant summary). The hierarchical
age-period-cohort (HAPC) model introduced by Yang and Land (2006,
2008) emerges as an alternative modelling strategy for disentangling age,
cohort and period effects. Given that each respondent's age can be viewed
as embedded within contextual cohort and period units, it offers a poten-
tially useful method to investigate APC effects. It is suited for repeated
cross-sectional surveys, as is the case for this study.

However, hierarchical models fundamentally operate within a linear
regression framework, in which one or more variables (typically cohort
and period) are assumed to be random effects. This assumption of uncor-
related cohort and/or period effects poses challenges if either cohort or
period exhibits some degree of correlation when the dependent variable
demonstrates a continuous upward or downward trend over the entire
data period. As is often the case with turnout data (Achen and Wang
2019), estimates derived from HAPC models may be biased and mislead-
ing (Bell and Jones 2018). For this study, I thus follow the conventional
approach constraining at least one of the parameters (Neundorf and
Niemi 2014) while reporting the results of HAPC models in the Online
Appendix.⁹

Following the approach of Bhatti and Hansen (2012), this study classi-
fies individuals into six generational categories: the Pre-war generation,
the Baby-boomer generation, the 60s generation, the 70s generation, the
80s generation, and the 90/00s generation (see Table 2). It resorts to a
relatively general classification framework which recognises the electoral
participation disparity between pre- and post-baby boomers (Blais et al.
2004; Franklin 2004; Gallego 2009; Wass 2007a, 2007b) while enables the
observation of general turnout development among post-baby boomers.

Theoretically, the 80s generation spent most of its formative years in
the post-Maastricht period, during which the policy and geographical
scope of the EU dramatically widened. Milestones such as the establish-
ment of the European Central Bank and the introduction of the euro
marked notable developments during this period. On the other hand, the
90/00s generation spent most of its formative years when European issues
gained prominence through a series of EU crises, including the sovereign
debt crisis, the migrant crisis and Brexit. Given the widened role of the
EU and the changing electoral contexts of EP elections at the turn of the

<table><caption>**Table 2.** Categorisation of generations.¹⁰</caption><thead><tr><th></th><th>Pre-war</th><th>Baby-boomer</th><th>60s</th><th>70s</th><th>80s</th><th>90/00s</th></tr></thead><tbody><tr><th>Year of birth</th><td>-1945</td><td>1946-1959</td><td>1960-1969</td><td>1970-1979</td><td>1980-1989</td><td>1990-</td></tr><tr><th>Formative years</th><td>-1963</td><td>1964-1977</td><td>1978-1987</td><td>1988-1997</td><td>1998-2007</td><td>2008-</td></tr></tbody></table>
<figure><img src="image_29.png" /></figure>

twenty first century, shifting turnout patterns in supranational elections across generations are expected to occur across the 80s and the 90/00s generations coming of age during this period.

Extending the classification framework of Bhatti and Hansen (2012) serves two additional analytical utilities. First, it facilitates a parsimonious comparison between national and EP elections across countries, enabling the identification of pan-European turnout patterns across diverse European countries of national history and geographical position. Second, it allows comparisons of generational turnout patterns with previous studies that employ similar categorisations (e.g. Bhatti and Hansen 2012; Blais et al. 2004; Wass 2007b) by avoiding more technical generation classifications.

As the changing turnout pattern across generations is grounded in varying electoral contexts of EP elections in which younger cohorts come of age, the APC models include additional controls to account for the effects of compositional changes in social demography and political attitudes across generations. These control variables include gender, education, party identification, union membership, religious attendance, and occupational status.¹¹ While the educational level and occupational status are related to the resource model of political participation, party identification, union membership, and religious attendance are connected to the mobilisation model (Smets and van Ham 2013).

However, the EES and CSES have different scales and measures for religious attendance, occupational status, and education. These variables are harmonised to ensure consistency and comparability. Religious attendance and occupational status are dichotomised (i.e. never attending religious services or not; unemployed or not); for the analysis of voter turnout in national elections, the education variable groups individuals who reported a university education in the CSES with those who reported completing education or still studying after the age of 20 in the EES.¹²

Although the main interest of this study lies in the identification of overall turnout patterns across generations in Europe, studies suggest differences in participation patterns in EP elections between Western and Eastern Europe (Flickinger and Studlar 2007), as well as voting behaviour in general. Consequently, pooled APC models across 28 European countries are complemented by models splitting EU member states into two main blocks: those in Western Europe (grouped as the EU-15) and those in Eastern Europe (labelled as the non-EU-15).

In addition to estimating the turnout gap between national and EP elections across generations by directly comparing predicted voting probabilities, multinomial logistic regressions are employed to identify the effect of generation on the likelihood of individuals falling into different turnout patterns in national and European elections. With information on
<figure><img src="image_30.png" /></figure>

voters' participation or abstention in both a given EP election and its previous (or concurrent) national election, respondents in each wave of the EES are categorised into four groups: (1) voters (i.e. those who participate in national and EP elections), (2) EP-only abstainers (i.e. those who participate in national elections but not in EP elections), (3) EP-only voters (i.e. those who abstain in national elections but not in EP elections), and (4) habitual abstainers (i.e. those who abstain in national and EP elections). As studies have demonstrated that the behaviour of participating in domestic contests but not in supranational arenas is a consequence of the demobilising effects of Eurosceptic and indifferent attitudes (Schäfer 2021), the APC multinomial analysis controls for attitudes towards EU membership and levels of political interest.

# Results

## Diverging generational participatory patterns in national and EP elections

### Turnout patterns in EP elections across generations

Logistic regressions on electoral participation in EP elections examine whether the probability of voting in supranational contests declines from earlier cohorts to younger cohorts (H1) while controlling for age and period effects. Regarding period effects, the 2019 EP elections had positive effects on turnout in most of the EU member states. Voters across all ages were generally more likely to participate in the 2019 EP elections than the 2014 EP elections, except for Sweden (see Online Appendix Figure 2 for the effects of period on turnout in EP elections). Recent analysis has ascribed, at least partly, the increased turnout in the 2019 EP elections to the mobilising effects of transnational policy issues such as environmental protection (Braun and Schäfer 2022).

Turning to the generational participatory pattern in EP elections, Figure 3 plots and compares the effect of generation on turnout. With age and period effects controlled for, younger generations are not monotonously less likely to participate in supranational elections. The 80s and 90/00s generations socialised in the expanded reach of the EU and increased salience of European issues do not show a consistent decline in participatory levels, while a continuous decline in turnout levels is evident among earlier generations.

Rising participation among younger generations coming of age at the turn of the twenty first century is more evident among the EU-15. The reversed participatory pattern among younger cohorts is more pronounced when accounting for compositional changes in social demography and political attitudes across generations. Comparing the odds ratios estimated
<figure><img src="image_31.png" /></figure>

<figure><img src="image_32.png" /><figcaption>Figure 3. Predicted probabilities of turnout in European Parliament elections by generation.</figcaption></figure>

Note: The figure compares the estimated effect of generation based on Models 1 to 6 in Online Appendix Table 1. It displays the marginal effect of generation on the likelihood of turnout in EP elections while holding all other variables constant at their mean or baseline values. The upper and lower bounds represent the 95% confidence intervals.

from the model with control variables across the EU-15 reveals a reversing participatory pattern across younger generations. While the voting likelihood of the 70s generation significantly decreases by 31% compared to that of the Pre-war generation, it declines only by 25% for the 80s generation and 13% for the 90/00s generation (see Model 2 in Online Appendix Table 1).

Although there is no firm evidence of rising participation among younger cohorts in the non-EU-15 member states, a consistent decline in turnout across the two youngest cohorts is neither observable. According to the odds ratios estimated from the model with control variables across the non-EU-15, the voting likelihood of the 70s generation significantly decreases by 39% compared to that of the Pre-war generation; it declines by 50% for the 80s generation but 48% for the 90/00s generation (see Model 4 in Online Appendix Table 1).

Across models, age typically exerts a curvilinear effect on turnout. The likelihood of voting generally increases as individuals age and then gradually decreases around their seventies (see Online Appendix Figure 3 for the effect of age on turnout in EP elections). Regarding control variables, being a male, obtaining higher education (or still studying), identifying with any political party, having union membership, attending religious services, and not being unemployed have consistently significant and positive effects on turnout in EP elections across all models.

## Turnout patterns in national elections across generations

Logistic regressions on electoral participation in national first-order elections test whether the probabilities of voting in domestic contests decline from earlier cohorts to younger cohorts (H2) while controlling for age
<figure><img src="image_33.png" /></figure>

and period effects. Figure 4 plots and compares the effect of generation on turnout in national first-order elections. In contrast to the changing generational participatory patterns identified in EP elections, a general decline in turnout levels across generations is observed in domestic contests.

Comparing the odds ratios estimated from the model with control variables across the EU-28 demonstrates a continuous decline in the probabilities to vote in national first-order elections across generations. While the voting likelihood of the 70s generation significantly decreases by 31% compared to that of the Pre-war generation, it further declines by 41% for the 80s generation and 45% for the 90/00s generation (see Model 6 in Online Appendix Table 2).¹³

A significant and curvilinear effect of age is consistently found across all models in domestic elections. While the probability of voting increases when individuals grow up, it begins to decrease during individuals' mid to late 50s (see Online Appendix Figure 4 for the effect of age on turnout in national elections). Regarding control variables, education, party identification, union membership, religious attendance, and unemployment consistently affect turnout in national elections across all models. However, gender is not a significant variable in non-EU-15 member states, which somewhat echoes studies showing the effect of gender is relatively less consistent on electoral participation (Smets and van Ham 2013).

In summary, the probability of voting does not decline from earlier cohorts to later cohorts in EP elections across the EU-28. Notably, younger generations across the EU-15 are showing a growing tendency to participate in EP elections compared to their generational counterparts among post-baby boomers. While aggregate turnout in EP elections has been adversely impacted by the replacement of the Pre-war and Baby-boomer

<figure><img src="image_34.png" /><figcaption>**Figure 4.** Predicted probabilities of turnout in national elections by generation.</figcaption></figure>

Note: The figure compares the estimated effect of generation based on Models 1 to 6 in Online Appendix Table 2. It displays the marginal effect of generation on the likelihood of turnout in national elections while holding all other variables constant at their mean or baseline values. The upper and lower bounds represent the 95% confidence intervals.
<figure><img src="image_35.png" /></figure>

generations with later cohorts, this negative effect is less prominent through generational replacement among post-baby boomers. In contrast, the probability of voting continues to decline from earlier cohorts to later affiliates in national elections across European democracies, confirming the ‘negative’ effects of generational replacement on aggregate turnout identified in the existing literature (Blais et al. 2004; Gallego 2009; Konzelmann et al. 2012; Wass 2007a, 2007b).

## Narrowing turnout gap between national and European elections across generations

Two empirical strategies are adopted to assess whether the gap in turnout between national and EP elections narrows across younger generations and whether it can be explained by a decreasing likelihood of becoming an EP-only abstainer among younger cohorts (H3). Figure 5 contrasts the estimated propensity to vote in national and EP elections across generations.

Whereas the probability of participating in national first-order elections consistently outweighs supranational contests, suggesting the enduring significance of national elections over European ones among voters from all cohorts, the dynamics of the turnout gap vary to some degree across generations. A general trend towards a narrower gap in turnout between domestic and supranational elections is observable among younger cohorts, suggesting an increasing salience of EP elections relative to national contests in the view of younger voters. Yet, the tightening turnout gap at the national and EU levels across younger generations is more pronounced across the EU-15.

The results of multinomial regression models are presented to contrast how voters from various cohorts participate and abstain differently in each EP election and its previous (or concurrent) national election. Figure 6 compares the effect of generation on four turnout varieties based on reported participation and abstention in national and supranational contests. Consistent with the narrowing turnout gap between domestic and supranational elections across younger cohorts, a decreasing likelihood of becoming EP-only abstainers is observable among individuals from younger generations.

In the EU-15, the probability of becoming an EP-only abstainer increases from the Pre-war generation to the 60s generation, contributing to the widened turnout gap among earlier generations. On the other hand, the probability of becoming an EP-only abstainer begins to decrease among cohorts following the 60s generation, partly explaining the narrowing turnout gap across younger cohorts. Furthermore, younger cohorts following the 70s generation are increasingly more likely to participate in both national and EP elections while less likely to become habitual
<figure><img src="image_36.png" /></figure>

<figure><img src="image_37.png" /><figcaption>**Figure 5.** Turnout gap between national first-order and European elections by generation.</figcaption></figure>

Note: The figure compares the effect of generation estimated based on Models 2, 4, and 6 in Online Appendix Tables 1 and 2 with control variables of social demography and political attitudes. It displays the marginal effect of generation on the likelihood of turnout in EP and national first-order elections while holding all other variables constant at their mean or baseline values. The upper and lower bounds represent the 95% confidence intervals. The turnout gap is calculated by deducting the predicted probabilities of voting in EP elections from national ones by generation.

<figure><img src="image_38.png" /><figcaption>**Figure 6.** Predicted probabilities of participation and abstention in European and national elections across generations.</figcaption></figure>

Note: The figure compares the estimated effect of generation based on Models 1 and 2 from Online Appendix Table 3. It displays the marginal effect of generation on the likelihood of falling into one of the four categories based on participation and abstention in a given EP election and its previous (or concurrent) national election while holding all other variables constant at their mean or baseline values. The upper and lower bounds represent the 95% confidence intervals.

abstainers. Turning to the non-EU-15 member states, the decrease in the likelihood of becoming an EP-only abstainer is observable among the 90/00s generation.

Across all multinomial models, age exerts a consistent curvilinear effect on the likelihood of falling into one of the four categories. Compared to being EP-only abstainers, the probability of voting in both national and EP elections increases as individuals age, but it decreases when voters reach old age; on the contrary, the likelihood of being habitual abstainers
<figure><img src="image_39.png" /></figure>

and EP-only voters decreases as individuals age and increases again when voters reach old age (see Online Appendix Table 3 for statistical results). Lastly, party identification, union membership, religious attendance, not being unemployed, and political interest positively affect the likelihood of participating in both national and EP elections compared to being EP-only abstainers; conversely, low educational levels and Eurosceptic attitudes significantly decrease the probability of participating in both national and EP elections compared to being EP-only abstainers (see Online Appendix Table 3 for statistical results).

In summary, there is an observable trend of a narrowing gap in turnout between national and European elections among younger cohorts across the EU-28, with a more pronounced pattern among the EU-15. The changing dynamics of this turnout gap at the national and EU levels indicate a shifting significance between these election types for individuals socialised in different electoral contexts. The tightening gap in turnout between national and supranational elections across younger generations is underscored by their decreasing likelihood of participating in national elections while abstaining in European contests.

## Conclusions

In the existing literature, an overall decline in voter turnout during the second half of the twentieth century has been partially attributed to the adverse effects of generational replacement (Blais et al. 2004; Franklin 2004; Kostelka and Blais 2021). Turnout has arguably declined as younger generations less prone to cast a vote have replaced earlier generations more likely to turn out, with a significant turnout gap between pre- and post-baby boomers widely identified (Bhatti and Hansen 2012; Gallego 2009; Wass 2007a, 2007b). Whereas scholars had previously anticipated a continued electoral decline in EP elections based on lower participatory levels among post-baby boomers (Bhatti and Hansen 2012), the 2019 EP election surged to its highest participatory level in the last two decades. Immediate analysis of the 2019 EP elections has, at least partly, ascribed the increased turnout to increased participation among young citizens (Becewe et al. 2019).

This study presents evidence that the increased turnout in the 2019 EP election is partly driven by positive period effects influencing voters across all ages in most of the EU member states, compared to the 2014 EP election. Yet, investigating generational participation patterns in supranational elections shows that younger cohorts are not monotonously less likely to vote in EP elections when compared to their generational counterparts. This indicates additional factors at play influencing turnout development in recent EP elections through changes in generational composition.
<figure><img src="image_40.png" /></figure>

A discernible increase in participation is observed among younger cohorts in supranational contests within the EU-15. The changing generational participatory pattern in EP elections is arguably linked to the shifting socialisation experiences of these cohorts in the expanded reach of the EU and the heightened significance of European issues at the turn of the twenty first century. In contrast, electoral participation in national arenas is consistently influenced by the enduring negative impacts of generational turnover, contributing to a gradual erosion of turnout. Moreover, an overarching trend indicates a narrowing turnout gap between national and European elections across younger cohorts. This shift can be explained by a decreasing likelihood of participating in national elections while abstaining from supranational contests among individuals from more recent cohorts.

The reversal in generational participation trends in EP elections, driven by increased turnout among younger cohorts in Western Europe, sheds light on the ‘negative’ impacts of generational replacement on overall turnout (Blais et al. 2004; Franklin 2004; Gallego 2009; Wass 2007a, 2007b). This prompts a careful reading of scholarly predictions regarding aggregate turnout grounded in previously estimated effects of generational replacement (Bhatti and Hansen 2012; Konzelmann et al. 2012). In examining turnout dynamics between national and supranational elections, this study contributes broadly to the changing character of present-day EP elections (Schäfer 2021; Schmitt et al. 2020). It provides a fresh analytical perspective centred on cohort differences, questioning the temporal robustness of the SOE model. While the SOE model remains the cornerstone of European electoral studies, its theoretical underpinnings appear less applicable among younger generations. The diminishing turnout gap between national first-order and supranational elections among younger cohorts highlights the increasing significance of EP elections across both election types and generations. Although participatory levels remain consistently lower in EP elections than in national contests, increased participation in supranational elections but not in domestic arenas among younger cohorts suggests a relatively ‘more-at-stake’ perception of EP elections among the youth.

The diverging generational turnout patterns between European and national elections hint at different trends of participatory inequalities. Whereas turnout in supranational elections consistently lags behind national elections, there is a glimmer of hope in the increasing youth involvement in European contests. This resurgence in participation among the young brings encouraging news for scholars and authorities grappling with concerns over the legitimacy of the EU. Conversely, the ongoing erosion of turnout in national elections across generations serves as a warning sign for national governments, suggesting a downward trajectory of
<figure><img src="image_41.png" /></figure>

voter turnout in the decades to come. Changing participation patterns across generations illuminate the shifting dynamics in elections that continue to be brought about through generational replacement in European democracies.

## Notes

1. See also Bhatti et al. (2012) and Sciarini et al. (2001) where the relationship between age and turnout resembles a ‘roller-coaster’ ride. Their studies, based on verified turnout data from Finland, Denmark, Texas, and the canton of Geneva, observe a decline in turnout during the initial years following young citizens’ acquisition of the franchise.

2. Bhatti and Hansen (2012) had considered an alternative scenario in which turnout in EP elections among future generations (those born after 1991) surges by 10%, in contrast to those born between 1980 and 1991. This results in a less pronounced but still negative projection of a -0.9% turnout change from 2009 to 2020. Furthermore, according to their predictions, the anticipated decline in turnout during the period from 2020 to 2040 is expected to be more substantial compared to the period from 2009 to 2020.

3. According to the data collected from individual-level registrations in both the 2015 and 2019 Finnish parliamentary elections, Nemčok and Wass (2021) demonstrate that there has been a rise in turnout among younger age groups in Finland.

4. However, turnout information is unavailable in the EES 2004 dataset in Belgium, Latvia, Lithuania, and Malta. In addition, age information is missing in Luxembourg in the EES 2004 dataset.

5. See Online Appendix Tables 7 and 8 for statistical results with weighted data and Online Appendix Figures 6 and 7 for predicted probabilities of turnout by generation with weighted data.

6. I additionally included the cubed term of age variable to potentially account for the roller-coaster relationship between age and turnout (Bhatti et al. 2012). The substantive results remain similar (see Online Appendix Figure 5).

7. I have checked for multicollinearity. Except for age and its squared term, the adjusted generalised standard error inflation factor (aGSIF) remains below 1.6. Fox and Monette (1992) advocate for the use of a GSIF, particularly when dealing with categorical predictors featuring more than two levels (e.g. cohorts and country-year dummies in this analysis). This adjustment accounts for the number of levels, allowing comparability with other predictors. When employing the aGSIF, we must take the square-root of our benchmarks for what constitutes a large value – aGSIF values above $\sqrt{2.5}$ (1.6) may warrant attention, while values exceeding $\sqrt{5}$ or $\sqrt{10}$ (2.2 or 3.2) indicate a more substantial concern of multicollinearity.

8. The aim of this study is to identify and compare the effect of generations on turnout in national and EP elections across EU member states. Whereas it may be relevant to employ hybrid models including age X period and generation X period interactions to fully understand the time-related development in turnout (Nemčok and Wass 2021), it is beyond the interest of this study.

9. Similar to the Yang-Land HAPC specification, the HAPC models nest individuals in cohort and country-year units (see Online Appendix Tables 9
<figure><img src="image_42.png" /></figure>

and 10 for statistical results and Online Appendix Figures 8 and 9 for ran-
dom effects for cohort units).

10. It is important to note that the generational classification framework employed in this study does not aim to identify ‘political generations’ in the term of Mannheim (1928).

11. I additionally control for political interest. The generational participation pattern in EP elections remains similar (see Online Appendix Table 5 for statistical results). Yet, the variable of political interest is not consistently available in the CSES M1–5.

12. The education variable is harmonised in the analysis of turnout in national first-order elections as data are collected from the EES and CSES with different measures of educational levels. While the EES asked the age when respondents stopped full-time education with the category of still studying, the CSES recorded individuals' highest education attainment without the category of still studying. For comparability purposes, respondents reporting competing education or still studying after the age of 20 in EES are grouped with those reporting a university education in CSES.

13. While the CSES are administrated in the post-electoral contexts of national elections, turnout in the last national elections in the EES may be collected relatively distant in time from the last national elections. This may suggest contextual differences between the two surveys. I thus additionally control for survey sources to capture any survey-specific effects. Yet, the results remain similar despite these variations (see Online Appendix Table 6 for statistical results).

Acknowledgements

I am grateful to the special symposium editors, Wouter van der Brug and Sylvia Kritzinger, for their encouragement and constructive comments. I would also like to express my gratitude to Laura Morales, Romain Lachat, the ECPR workshop ‘Generations and Political Change’ participants, and the anonymous reviewers for their insightful suggestions on earlier versions of this article.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Notes on contributor

Chiao Li is a PhD candidate in comparative politics at the Centre for European Studies and Comparative Politics of Sciences Po (Sciences Po, CEE). He completed his research master's degree in political behaviour at Sciences Po, where he graduated with distinction. His doctoral research investigates the transformation of electoral participation and party preferences in Europe across generations.

[chiao.li@sciencespo.fr]

ORCID
<figure><img src="image_43.png" /></figure>

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