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Copy and paste formula below.


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Lunar cycle
===========
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{ Full/New Moon signals indicator MkVI }
{ Accurate to within 1 minute per 69 years }
{ ©Copyright 2002-2004 jose silva }
{ For personal use only }
{ http://www.metastocktools.com }

{ Plots +1 signal on Full Moon; -1 on New Moon }
{ If FM/NM falls on a holiday or weekend,
  signal is plotted on the nearest trading day }
{ Warning: will not plot last FM/NM signal
   until it is confirmed on next trade day }

{ Input your world time zone }
TZ:=Input("Your Time Zone?  (-12 to +12hrs)",
 -12,12,10);

{ Lunar cycle }
LunarMonth:=29.530589;
Offset:=7.254621;

{ Calendar }
leap:=Frac(Year()/4)=0 AND Frac(Year()/100)<>0
 OR Frac(Year()/400)=0;
y:=Year()*365+Int(Year()/4)
 -Int(Year()/100)+Int(Year()/400);
m:=
 If(Month()=2,31-leap,
 If(Month()=3,59,
 If(Month()=4,90,
 If(Month()=5,120,
 If(Month()=6,151,
 If(Month()=7,181,
 If(Month()=8,212,
 If(Month()=9,243,
 If(Month()=10,273,
 If(Month()=11,304,
 If(Month()=12,334,
 -leap)))))))))));
CurrentDay:=y+m+DayOfMonth()-TZ/24-Offset;

{ Full/New Moon }
FM:=Frac(CurrentDay/LunarMonth);
NM:=Frac(FM+0.5);

{ Plot in own window below chart }
(PeakBars(1,FM,.01)=0)-(PeakBars(1,NM,.01)=0)

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http://www.metastocktools.com



Are Investors Moonstruck? - Lunar Phases and Stock Returns
========================

http://papers.ssrn.com/sol3/Delivery.cfm/SSRN_ID283156_code010918600.pdf?abstractid=283156


Psychological evidence and casual intuition predict that lunar phases
regulate mood.

This paper investigates the relation between lunar phases and stock
market returns in 48 countries.  We find strong global evidence that
stock returns are lower on days around a full moon than on days around
a new moon.  The magnitude of the return difference is 6.6 percent per
annum from our 15-day window panel analysis.

The lunar effect is independent of other calendar-related anomalies such
as the January effect, the day-of-week effect, and the calendar month
effect.