MetaStock -> Tools -> Indicator Builder -> New
Copy and paste formula below.


==================
MACD, %-normalized
==================
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{ Normalized MACD % & histogram v3.0, -100~+100% }
{ ©Copyright 2003-2004 Jose Silva }
{ http://www.metastocktools.com }

pds1:=Input("short EMA periods",1,252,12);
pds2:=Input("long EMA periods",2,2520,252);
pds3:=
 Input("MACD trigger signal periods",1,252,9);
pds4:=Input("normalizing periods (1=none)",
 1,2520,252);
x:=Input("use Open=1 High=2 Low=3 Close=4 Volume=5 P=6",1,6,4);
plot:=Input("MACD=1, Histogram=2, trigger crossover Signals=3",1,3,1);

x:=If(x=1,O,If(x=2,H,If(x=3,L,If(x=5,V,If(x=6,P,C)))));
sht:=Mov(x,pds1,E);
lng:=Mov(x,pds2,E);
ratio:=Min(sht,lng)/Max(sht,lng);
Mac:=(If(sht>lng,2-ratio,ratio)-1)*100;

MacNorm:=(Mac-LLV(Mac,pds4))
 /(HHV(Mac,pds4)-LLV(Mac,pds4)+.000001)*100;
MacNorm:=If(pds4<2,Mac,MacNorm);
trigger:=Mov(MacNorm,pds3,E);
hist:=MacNorm-trigger;
signals:=Cross(MacNorm,trigger)
 -Cross(trigger,MacNorm);

If(plot=1,trigger,0);
If(plot=3,signals,If(plot=2,hist,MacNorm))

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