Article dans une revue: Using monthly firm-level exports and imports over 1993–2020, we uncover four facts: (i) deviations of large exporters from the average growth rate explain a large share of aggregate fluctuations; (ii) an important source for these deviations is the top exporters’ higher loadings on common shocks; (iii) the stronger reaction of the top 1% exporters to the GFC and Covid crises contributed to the export collapses; (iv) a higher elasticity to large demand shocks, not a different exposure to global value chain shocks, contributes to this stronger reaction. The results show that idiosyncratic reactions of large firms to common shocks matter for aggregate export fluctuations, and are especially relevant for the trade collapses of the 2008/2009 crisis and the Pandemic.