Time-frequency connectedness between food commodities: New implications for portfolio diversification

Abstract

This study examines the time-frequency connectedness of food commodities (cereals, dairy, food, meat, vegetable oil, and sugar) in the Food and Agriculture Organization's world food indices. With a monthly-frequency dataset covering February 1990 to October 2021, we utilise the returns spillover index approach of Baruník and Křehlík (2018). The results are robust to the time-varying parameter vector autoregressive (TVP-VAR) connectedness approach. The findings explicate that food commodities are highly connected in the short- and long-term horizons. The dynamic total connectedness varies from 15% to 80% in the short term, 1% to 70%, in the medium-term, and 1% to 75% in the long-term, with high fluctuations in notable crisis periods. Contagious returns spillovers between food commodities are propagated by vegetable oil. Diversification and safe-haven properties of food commodities are consistently found in the meat market across tranquil and exuberant trading periods, respectively. The safe-haven role of sugar in recent episodes of financial crises is highlighted by our findings. The economic, policy, and portfolio implications of our results are discussed.