BZH=100*GetRTDataForeign("Change","BZH")/GetRTDataForeign("Prev","BZH"); //percentage
change since yesterday's close
BHS_BZH_trigger=2; //trigger value
AlertIf(Ref(Cross((BHS-BZH),BHS_BZH_trigger),-1),"SOUND
D:\\AmiBroker\\Sounds\\alert.wav","Signal Alert on pair BHS-BZH (up)",1);
AlertIf
(Ref(Cross(-1*(BHS+BZH),BHS_BZH_trigger),-1),"SOUND
D:\\AmiBroker\\Sounds\\alert.wav","Signal Alert on pair BHS-BZH (down)",1);