Here's a link to a sample file with the implemented construct:
http://www.savefile.com/files/4522483
File: Compare Neg n Pos Nos_ChomKrusopon_wksht.xls
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Rgds
Max
xl 97
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GMT+8, 1° 22' N 103° 45' E
xdemechanik <atyahoo<dotcom
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