      Because everyone else does. This is half a joke, but half true. Sectorrotation is as old as the sectors themselves. Depending upon the news dujour, different sectors are in play. Sometimes it is the Internet sector,sometimes the Banking sector, the Oil sector. Transportation sector.Hardware sector, or the Biotech sector. The rotation is initiated by newsevents and is followed by the bandwagon effect of fund managers followingthe herd. Finally, once the sector really heats up, the story hits thecover of Business Week, and the retail investors pile in. It is at thispoint that the big money looks elsewhere, and the cycle begins anew.