On Sat, 16 Jun 2007, in microsoft.public.excel.charting,
Andy Pope said:

The formula for X value of NotchLeft is
=MEDIAN($A$1:$A$50)-(1.7*((1.25*(PERCENTILE($A$1:$A$50,0.75)-PERC
ENTILE($A$1:$A$50,0.25))/(1.35*50))))

The formula for X value of NotchRight is
=MEDIAN($A$1:$A$50)+(1.7*((1.25*(PERCENTILE($A$1: $A$50,0.75)-PERC
ENTILE($A$1:$A$50,0.25))/(1.35*50))))

Any particular reason for preferring
PERCENTILE(<range,0.75)-PERCENTILE(<range,0.25)
to
QUARTILE(<range,3)-QUARTILE(<range,1)
?

(I'm such a fond user of quartiles that I sometimes use them instead on
MIN, MAX and MEDIAN, because the five values are so simple to copy down
a column next to the numbers 0-4)

--
Del Cotter
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