Paul,

As David explained, an OR is required, expressed indicatively as:
((Cond1)+(Cond2)+(Cond3)+...)

Hence the part in your expression should look like this:
.... *(('Grid data'!F2:F4557="NS")+('Grid data'!F2:F4557="C")+
(TRIM('Grid data'!F2:F4557)="")))
--
Max
Singapore
http://savefile.com/projects/236895
xdemechanik
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