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


======================
Calendar Week of Month
======================
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{ Calendar-absolute Week-of-Month signals }
{ Plot on own window below chart }
{ ©Copyright 2004 Jose Silva }
{ http://www.metastocktools.com }

WeekOfMonth:=Input("[1]st  [2]nd  [3]rd  [4]th  [5]th  week in month",1,5,1);
plot:=Input("[1]Week signals,  [2]Week count",
 1,2,1);

d:=DayOfMonth();
weekNr:=If(d<=7,1,
 If(d>7 AND d<=14,2,
 If(d>14 AND d<=21,3,
 If(d>21 AND d<=28,4,5))));
signal:=weekNr=WeekOfMonth;

If(plot=1,signal,WeekNr)

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