Miners .AXMM dropped 2.7%, with iron ore behemoths BHP BHP.AX, Rio Tinto RIO.AX and Fortescue FMG.AX shedding more than 2% each. May 6 (Reuters) - Australian shares fell 2% on Friday to hit a seven-week trough, as investors dumped equities across the board on concerns that aggressive central bank policies around the globe to contain broadening inflation pressures could hurt economic growth. Macquarie Group MQG.AX declined 5.6% after it warned of significantly lower income from its commodities trading arm and forecast transaction activity at its capital business to ease from record levels in the near term.