DV2 for Amibroker (AFL)

function PercentRank( Data, Periods )
{
Count = 0;
for ( i = 1; i < Periods + 1 ; i++ )
{
Count = Count + IIf ( Ref( Data, 0 ) > Ref( Data, -i ), 1, 0 );
}
return 100 * Count / Periods;
}

a1 = Close / ((H+L)/2);
a2 = Ref(Close,-1) / ((Ref(H,-1)+Ref(L,-1))/2);
DVu = ((a1+a2)/2)-1;
DVb = PercentRank( DVu, 252 );
Plot( DVb, "DV(2)", colorRed);
//}

Plot(40,"",colorGreen);
Plot(70,"",colorRed);