A Longitudinal Analysis of Topic Diversity in Swiss Press Coverage

Topic diversity in news coverage is widely considered central to the functioning and cohesion of contemporary democracies. Currently, however, the news media as a central arena for public discourse face increasing economic pressures. A frequently expressed concern is that these developments lead to a decrease in topic diversity in news coverage, especially during societal crises such as the COVID-19 pandemic. However, empirical evidence remains ambiguous, and longitudinal research is scarce. This study addresses this gap by investigating how topic diversity in the Swiss press developed between 1998 and 2024. Using BERTopic topic modeling to identify topics inductively in 1,635,589 articles from three major Swiss newspapers, we find considerable changes. Results show a phase of stable topic diversity until the mid-2010s, followed by a slow decrease and a substantial drop in topic diversity with the onset the COVID-19 pandemic. Overall, this study partially supports the notion of a decline in topic diversity in news coverage, while also highlighting the influence of major societal crises. These findings warrant a critical discussion regarding financial resources for journalism and journalistic practice during societal crises.