Here’s a concept I thought about whilst on holidays:

Forward reference (shift backwards on charts) and center a Moving Average, then extend and project the last known MA direction into the future.

This method gets around the no-plot in null (N/A) zone limitation in MetaStock, and can apply to any indicator or oscillator on charts or separate windows.

MetaStock -> Tools -> Indicator Builder -> New ->
Copy and paste complete formula between “—8<—” lines.

=============
MA – centered
=============
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{ Centered Moving Average – v3.0 }
{ Uses forward-referencing to center Mov Avg
and project future direction.}
{ Uses hindsight – do not trade! }

{ ©Copyright 2005 Jose Silva
For personal use only.
}

{ User inputs }
fwPds:=Input(“Forward-referencing periods (automatic = -1)”,-1,2600,-1);
proj:=Input(“Project last known MA: [1]Direction, [2]Value”,1,2,1);
pds:=Input(“Mov Avg periods”,1,2600,21);
type:=Input(“[1]EMA [2]SMA [3]TmSr [4]Tri [5]Var [6]Vol [7]Wght”,1,7,2);

{ Choose MovAvg type:
1 – Exponential MA
2 – Simple MA
3 – Time Series MA
4 – Triangular MA
5 – Variable MA
6 – Volume adjusted MA
7 – Weighted MA }
ma:=
If(type=1,Mov(C,pds,E),
If(type=2,Mov(C,pds,S),
If(type=3,Mov(C,pds,T),
If(type=4,Mov(C,pds,TRI),
If(type=5,Mov(C,pds,VAR),
If(type=6,Mov(C,pds,VOL),
Mov(C,pds,W)))))));

{ Automatic period-centering }
center:=LastValue(If(fwPds<0,Int(pds/2),fwPds));

{ Forward-referenced MovAvg }
fwd:=Ref(ma,center);

{ Last valid MovAvg plot point }
lastVal:=IsUndefined(fwd)
AND Alert(IsUndefined(fwd)=0,2);

{ Extend MovAvg plot into future null zone }
xtend:=LastValue(fwd+PREV-PREV);

{ Restrict invalid initial MovAvg plot }
movAvg:=Ref(Ref(xtend,pds-1),-pds+1);

{ Last MA known direction & future projection }
init:=Cum(IsDefined(movAvg))=1;
direction:=movAvg+
( ValueWhen(1,init OR lastVal,Ref(movAvg,-1))
-ValueWhen(1,init OR lastVal,Ref(movAvg,-2)))
*(BarsSince(init OR lastVal)+1);

{ Plot MovAvg on price chart }
If(proj=1,direction,movAvg)

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