Within a two-step GARCH framework we explore the linkages between equity returns of ten sectors in the euro area, the United States and Japan, respectively. Our estimation framework allows a distinction to be made between spillover effects originating from one of the three currency areas and intrasectoral spillover effects. We use daily data from the period between January 1986 and October 2002.
We find that, during the late 1990s, the worldwide importance of European equity markets has increased considerably. More precisely, price innovations in European equities (both aggregate returns and sector returns) have doubled or tripled their impact on other stock markets. At the same time, there is evidence that sectors have become more heterogeneous in each of the three currency areas, ie the response to aggregate shocks has increasingly varied across sectors. Spillover effects of aggregate market innovations have generally outweighed intra-sectoral spillover effects. Overall, the process towards higher integration has been primarily a phenomenon of equity markets in the euro area and the United States.