Determinants of the decision to build up excessive food stocks in the COVID-19 crisis.

In 2020, the first COVID-19 lockdowns resulted in food panic buying and excessive food stockpiling across many countries around the world. Many governments recommend keeping emergency food stocks for three to ten days for times of potential shortages in food supply. Based on data from an online survey conducted among Swiss inhabitants, we investigated the effect of knowledge level and stockpiling behaviour according to governmental stockpiling recommendations in normal times on the decision to build up more food stocks than usual during the first lockdown in 2020. For this purpose, we applied a combination of latent class analysis and logistic regression. Latent classes were constructed based on knowledge level and stockpiling behaviour according to governmental stockpiling recommendations in normal times. Subsequently, the information on class membership was used as predictor of the decision to excessively stockpile food during the first lockdown. The variable "class membership" revealed that respondents with a low knowledge level and food stocks below governmental recommendations in normal times had a 7.6 percentage points lower probability of excessively stockpiling food during the first lockdown than respondents with a high knowledge level and recommended food stocks in normal times. Excessive stockpiling was additionally driven by the worry that certain food products would disappear from the supermarket shelves entirely or would be in short supply. Moreover, regression results revealed that respondents who reduced their shopping frequency during the first lockdown in 2020 showed a higher probability of building up more food stocks than usual. Our findings are crucial for food suppliers and policymakers to understand the drivers of panic buying and to prevent this phenomenon in future crises.