Try this amended version of Duke's suggestion:

=IF(SUM(IF(City="New York",TotalInv,0))=0,0,SUM(IF(City="New
York",Sold,0))/SUM(IF(City="New York",TotalInv,0)))

Alternatively, perhaps a slightly shorter version
which returns blank: "" instead of zero:

=IF(SUM(IF(City="New York",TotalInv))=0,"",SUM(IF(City="New
York",Sold))/SUM(IF(City="New York",TotalInv)))
--
Rgds
Max
xl 97
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GMT+8, 1° 22' N 103° 45' E
xdemechanik <atyahoo<dotcom
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