The Asymmetric Impact of Global Economic Policy Uncertainty on International Grain Prices

Using monthly data from January 1998 to May 2021, this study investigates the asymmetric impact of global economic policy uncertainty on international grain prices by using nonlinear autoregressive distribution lag (NARDL). We find that there is a positive relationship between global economic policy uncertainty (GEPU) and international grain prices, and the relationship is asymmetric. Specifically, global economic policy uncertainty has a greater negative impact on wheat and maize prices than a positive impact, and a positive impact on soybean price is greater than negative one. We have also observed that the asymmetric impact of global economic policy uncertainty on rice price is not significant in the long-run. The findings have important implications for us to formulate targeted and differentiated international grain price regulatory policies