Help with Formula Please (Display text if no value exists)

I'm trying to calculate a number using multiple cells and the vloopup function (as shown in formula below). If no value exists it's returning "#VALUE!" in the cell, if a value exists then it works fine and gives me the correct number, however whenever no value exists I want it to display "N/A" or "-".

The current formula...
=($C$10/2)/COS($C$11*(PI()/180))*$C$16*VLOOKUP('Data Tables'!A13,'Data Tables'!A15:I22,7)

I have tried;
IF(ISNA(($C$10/2)/COS($C$11*(PI()/180))*$C$16*VLOOKUP('Data Tables'!A13,'Data Tables'!A15:I22,7)),"-",($C$10/2)/COS($C$11*(PI()/180))*$C$16*VLOOKUP('Data Tables'!A13,'Data Tables'!A15:I22,7))

But for some reason can't get it to work...

Any suggestions?

Thanks

http://www.mrexcel.com/forum/showthread.php?t=542057

Kynan,

Please take a few minutes to read the forum rules about cross posting.

http://www.mrexcel.com/forum/showthread.php?t=542057

Hi Hynan,

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